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Page 1: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 2: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 3: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 4: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 5: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 6: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 7: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 8: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Today’s Outline - November 30, 2015

• Rolling dice example

• Ideal gas

• Comparison of statistical models

• Blackbody radiation

• Chapter 5 problem requests

Please fill out course evaluation!

Final Exam:Monday, December 7, 14:00 – 16:00Room 204 SB

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 1 / 16

Page 9: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

To show how the degeneraciesbecome weighted to the cen-ter of the distribution, take thecase of rolling multiple 6-sideddice

Take, for example, 2 dice. Thepossible sums range from 2 to12 with multiplicities:

The total number of possibili-ties is 36 = 62.

For 3 dice, it becomes 216 = 63

Sum Mult.2 13 24 35 46 57 68 59 4

10 311 212 1

Sum Mult.3 14 35 66 107 158 219 25

10 2711 2712 2513 2114 1515 1016 617 318 1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16

Page 10: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

To show how the degeneraciesbecome weighted to the cen-ter of the distribution, take thecase of rolling multiple 6-sideddice

Take, for example, 2 dice. Thepossible sums range from 2 to12 with multiplicities:

The total number of possibili-ties is 36 = 62.

For 3 dice, it becomes 216 = 63

Sum Mult.2 13 24 35 46 57 68 59 4

10 311 212 1

Sum Mult.3 14 35 66 107 158 219 25

10 2711 2712 2513 2114 1515 1016 617 318 1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16

Page 11: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

To show how the degeneraciesbecome weighted to the cen-ter of the distribution, take thecase of rolling multiple 6-sideddice

Take, for example, 2 dice. Thepossible sums range from 2 to12 with multiplicities:

The total number of possibili-ties is 36 = 62.

For 3 dice, it becomes 216 = 63

Sum Mult.2 13 24 35 46 57 68 59 4

10 311 212 1

Sum Mult.3 14 35 66 107 158 219 25

10 2711 2712 2513 2114 1515 1016 617 318 1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16

Page 12: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

To show how the degeneraciesbecome weighted to the cen-ter of the distribution, take thecase of rolling multiple 6-sideddice

Take, for example, 2 dice. Thepossible sums range from 2 to12 with multiplicities:

The total number of possibili-ties is 36 = 62.

For 3 dice, it becomes 216 = 63

Sum Mult.2 13 24 35 46 57 68 59 4

10 311 212 1

Sum Mult.3 14 35 66 107 158 219 25

10 2711 2712 2513 2114 1515 1016 617 318 1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16

Page 13: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

To show how the degeneraciesbecome weighted to the cen-ter of the distribution, take thecase of rolling multiple 6-sideddice

Take, for example, 2 dice. Thepossible sums range from 2 to12 with multiplicities:

The total number of possibili-ties is 36 = 62.

For 3 dice, it becomes 216 = 63

Sum Mult.2 13 24 35 46 57 68 59 4

10 311 212 1

Sum Mult.3 14 35 66 107 158 219 25

10 2711 2712 2513 2114 1515 1016 617 318 1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16

Page 14: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

To show how the degeneraciesbecome weighted to the cen-ter of the distribution, take thecase of rolling multiple 6-sideddice

Take, for example, 2 dice. Thepossible sums range from 2 to12 with multiplicities:

The total number of possibili-ties is 36 = 62.

For 3 dice, it becomes 216 = 63

Sum Mult.2 13 24 35 46 57 68 59 4

10 311 212 1

Sum Mult.3 14 35 66 107 158 219 25

10 2711 2712 2513 2114 1515 1016 617 318 1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16

Page 15: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

and for 4 dice, 1296 = 64

Sum Mult.4 15 46 107 208 359 56

10 8011 10412 12513 140

Sum Mult.14 14615 14016 12517 10418 8019 5620 3521 2022 1023 424 1

0

2

4

6

8

10

12

14

16

18

0 20 40 60 80 100

Pro

ba

bili

ty

Normalized Count

2 dice

3 dice

4 dice

as N →∞ the distributionapproaches a Gaussisn

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 3 / 16

Page 16: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

and for 4 dice, 1296 = 64

Sum Mult.4 15 46 107 208 359 56

10 8011 10412 12513 140

Sum Mult.14 14615 14016 12517 10418 8019 5620 3521 2022 1023 424 1

0

2

4

6

8

10

12

14

16

18

0 20 40 60 80 100

Pro

ba

bili

ty

Normalized Count

2 dice

3 dice

4 dice

as N →∞ the distributionapproaches a Gaussisn

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 3 / 16

Page 17: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

and for 4 dice, 1296 = 64

Sum Mult.4 15 46 107 208 359 56

10 8011 10412 12513 140

Sum Mult.14 14615 14016 12517 10418 8019 5620 3521 2022 1023 424 1

0

2

4

6

8

10

12

14

16

18

0 20 40 60 80 100

Pro

ba

bili

ty

Normalized Count

2 dice

3 dice

4 dice

as N →∞ the distributionapproaches a Gaussisn

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 3 / 16

Page 18: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Example: Rolling dice

and for 4 dice, 1296 = 64

Sum Mult.4 15 46 107 208 359 56

10 8011 10412 12513 140

Sum Mult.14 14615 14016 12517 10418 8019 5620 3521 2022 1023 424 1

0

2

4

6

8

10

12

14

16

18

0 20 40 60 80 100

Pro

ba

bili

ty

Normalized Count

2 dice

3 dice

4 dice

as N →∞ the distributionapproaches a Gaussisn

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 3 / 16

Page 19: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square well

assuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )

=V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 20: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )

=V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 21: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )

=V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 22: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)

dk =1

8

4πk2dk

(π3/V )

=V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 23: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)

dk =1

8

4πk2dk

(π3/V )

=V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 24: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )

=V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 25: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 26: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 27: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 28: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 29: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk

= Ve−α(

m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 30: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk = Ve−α

(m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 31: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Ideal gas example

Treat an ideal gas as a 3D particle in an infinite square wellassuming non-interacting particles,the energy is

as before, we have a volume π3/Vper state in reciprocal space and thenumber of states in a shell of thick-ness dk is simply the degeneracy ofthe state with energy Ek

for distinguishable particles

Ek =~2

2mk2

~k =

(πnxlx,πnyly,πnzlz

)dk =

1

8

4πk2dk

(π3/V )=

V

2π2k2dk

Nn= dne−(α+βEn)

and the constraint that N =∑

Nn becomes

N =V

2π2e−α

∫ ∞0

k2e−β~2k2/2mdk = Ve−α

(m

2πβ~2

)3/2

e−α =N

V

(2πβ~2

m

)3/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 4 / 16

Page 32: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk

=3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 33: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk

=3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 34: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 35: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 36: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

E

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 37: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

E

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 38: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 39: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 40: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 41: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 42: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Significance of α and β

The constraint on the total energy, E =∑

NnEn becomes, in this context

E =V

2π2e−α

~2

2m

∫ ∞0

k4e−β~2k2/2mdk =

3V

2βe−α

(m

2πβ~2

)3/2

substituting for e−α obtained pre-viously

this is similar to the classical ther-modynamic expression for energyper molecule

we postulate that β is related to thetemperature

while α is related to the chemicalpotential

e−α =N

V

(2πβ~2

m

)3/2

E =3N

2βE

N=

3

2kBT

β =1

kBT

µ(T ) ≡ −αkBT

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 5 / 16

Page 43: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 44: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 45: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 46: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 47: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 48: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 49: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 50: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Particle distributions

It is conventional to divide the expressions for number of particles in astate by the degeneracy of the state to get an occupation fraction for eachstate and call the energy per state ε = En

Nn

dn= n(ε) =

[e(ε−µ)/kBT ]−1, Maxwell− Boltzmann

[e(ε−µ)/kBT + 1]−1, Fermi− Dirac

[e(ε−µ)/kBT − 1]−1, Bose− Einstein

if we apply the same constraints as before to identical fermions or bosonsin the 3-D infinite well, we obtain

N =V

2π2

∫ ∞0

k2

e [(~2k2/2m)−µ]/kBT ± 1dk

E =V

2π2~2

2m

∫ ∞0

k4

e [(~2k2/2m)−µ]/kBT ± 1dk

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 6 / 16

Page 51: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Comparison of statistics

The three statistics lead to very different behavior in occupation number

0

2

4

6

8

10

0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3

1 K50 K300 K

n(E

)

ε/µ

Maxwell-Boltzmann

0

2

4

6

8

10

0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 1.3

1 K

50 K

300 K

n(E

)

ε/µ

Bose-Einstein

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8 1 1.2 1.4

1 K50 K

300 K

n(E

)

ε/µ

Fermi-Dirac

Maxwell-Boltzmann: n(ε)→∞ as ε < µ and exponential behavior withtemperature

Bose-Einstein: occupation number is always infinite for ε < µ

Fermi-Dirac: n(ε) ≡ 1 as T → 0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 7 / 16

Page 52: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Comparison of statistics

The three statistics lead to very different behavior in occupation number

0

2

4

6

8

10

0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3

1 K50 K300 K

n(E

)

ε/µ

Maxwell-Boltzmann

0

2

4

6

8

10

0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 1.3

1 K

50 K

300 K

n(E

)

ε/µ

Bose-Einstein

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8 1 1.2 1.4

1 K50 K

300 K

n(E

)

ε/µ

Fermi-Dirac

Maxwell-Boltzmann: n(ε)→∞ as ε < µ and exponential behavior withtemperature

Bose-Einstein: occupation number is always infinite for ε < µ

Fermi-Dirac: n(ε) ≡ 1 as T → 0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 7 / 16

Page 53: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Comparison of statistics

The three statistics lead to very different behavior in occupation number

0

2

4

6

8

10

0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3

1 K50 K300 K

n(E

)

ε/µ

Maxwell-Boltzmann

0

2

4

6

8

10

0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 1.3

1 K

50 K

300 K

n(E

)

ε/µ

Bose-Einstein

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8 1 1.2 1.4

1 K50 K

300 K

n(E

)

ε/µ

Fermi-Dirac

Maxwell-Boltzmann: n(ε)→∞ as ε < µ and exponential behavior withtemperature

Bose-Einstein: occupation number is always infinite for ε < µ

Fermi-Dirac: n(ε) ≡ 1 as T → 0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 7 / 16

Page 54: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Comparison of statistics

The three statistics lead to very different behavior in occupation number

0

2

4

6

8

10

0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3

1 K50 K300 K

n(E

)

ε/µ

Maxwell-Boltzmann

0

2

4

6

8

10

0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 1.3

1 K

50 K

300 K

n(E

)

ε/µ

Bose-Einstein

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8 1 1.2 1.4

1 K50 K

300 K

n(E

)

ε/µ

Fermi-Dirac

Maxwell-Boltzmann: n(ε)→∞ as ε < µ and exponential behavior withtemperature

Bose-Einstein: occupation number is always infinite for ε < µ

Fermi-Dirac: n(ε) ≡ 1 as T → 0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 7 / 16

Page 55: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 56: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω

2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 57: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 58: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 59: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 60: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 61: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 62: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 63: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 64: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 65: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

Photons are bosons and so now we can use our understanding of quantumstatistics to compute the distribution of phonons in a rectangular box withthe following assumptions

1 The energy of a photon is ε = hν = ~ω2 The wave number is k = 2π/λ = ω/c

3 Only two spin states occur, s = 1 but m = ±1

4 The number of photons is NOT conserved

since the number of photons is notconserved, we can set µ → 0 andwe have

the degeneracy in terms of ω is

the energy density, Nω~ω/V in theinterval dω is

Nn=dn

e(ε−µ)/kBT − 1

Nω =dk

e~ω/kBT − 1

dk =V

π2c3ω2dω

ρ(ω)dω =~ω3dω

π2c3(e~ω/kBT − 1)C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 8 / 16

Page 66: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

0

2

4

6

8

10

12

14

0 0.5 1 1.5 2 2.5 3

Inte

nsity (

arb

.)

Wavelength (µm)

5000 K

4000 K

3000 K

ρ(ω) =~ω3

π2c3(e~ω/kBT − 1)

Universal curves with reducedtemperature

As ω → 0 (λ → ∞) dropsoff as λ−3 avoiding ultravioletcatastrophe

As ω → ∞ (λ → 0) dropsto zero exponentially, movingpeak position up in λ

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 9 / 16

Page 67: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

0

2

4

6

8

10

12

14

0 0.5 1 1.5 2 2.5 3

Inte

nsity (

arb

.)

Wavelength (µm)

5000 K

4000 K

3000 K

ρ(ω) =~ω3

π2c3(e~ω/kBT − 1)

Universal curves with reducedtemperature

As ω → 0 (λ → ∞) dropsoff as λ−3 avoiding ultravioletcatastrophe

As ω → ∞ (λ → 0) dropsto zero exponentially, movingpeak position up in λ

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 9 / 16

Page 68: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

0

2

4

6

8

10

12

14

0 0.5 1 1.5 2 2.5 3

Inte

nsity (

arb

.)

Wavelength (µm)

5000 K

4000 K

3000 K

ρ(ω) =~ω3

π2c3(e~ω/kBT − 1)

Universal curves with reducedtemperature

As ω → 0 (λ → ∞) dropsoff as λ−3 avoiding ultravioletcatastrophe

As ω → ∞ (λ → 0) dropsto zero exponentially, movingpeak position up in λ

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 9 / 16

Page 69: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Blackbody spectrum

0

2

4

6

8

10

12

14

0 0.5 1 1.5 2 2.5 3

Inte

nsity (

arb

.)

Wavelength (µm)

5000 K

4000 K

3000 K

ρ(ω) =~ω3

π2c3(e~ω/kBT − 1)

Universal curves with reducedtemperature

As ω → 0 (λ → ∞) dropsoff as λ−3 avoiding ultravioletcatastrophe

As ω → ∞ (λ → 0) dropsto zero exponentially, movingpeak position up in λ

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 9 / 16

Page 70: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 71: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 72: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 73: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 74: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 75: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 76: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 77: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 78: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 79: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 80: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.9

(a) Suppose you put both electrons in a helium atom into the n = 2 statefrom which state the atom is ionized to He+. What would the energyof the emitted electron be?

(b) Describe, quantitatively, the spectrum of the helium ion, He+

(a) The energy of each electron in thehelium atom is given by

initially the total energy is

after the ionization the energy of theion is

the energy of the emitted electron is

(b) The He+ is a hydrogenic atom withZ = 2 so the spectrum is the sameas for the Hydrogen atom except for aprefactor of 4

E =Z 2E1

n2, Z = 2

Etot = 2 · 4E1

4= −27.2 eV

Eion =4E1

12= −54.4 eV

Ee = Etot − Eion = 27.2 eV

1

λ= 4R

(1

n2f− 1

n2i

)C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 10 / 16

Page 81: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 82: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s)

helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 83: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 84: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s)

beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 85: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 86: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p)

carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 87: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 88: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3

oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 89: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 90: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5

neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 91: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12

(a) Figure out the electron configurations for the firsttwo rows of the Periodic Table (up to neon).

(b) Figure out the corresponding total angular momenta,for the first four elements. List all the possibilitiesfor boron, carbon, and nitrogen

(a) hydrogen: (1s) helium: (1s)2

lithium: (1s)2(2s) beryllium: (1s)2(2s)2

boron: (1s)2(2s)2(2p) carbon: (1s)2(2s)2(2p)2

nitrogen: (1s)2(2s)2(2p)3 oxygen: (1s)2(2s)2(2p)4

fluorine: (1s)2(2s)2(2p)5 neon: (1s)2(2s)2(2p)6

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 11 / 16

Page 92: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0,S = 0,

J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 93: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2

−→ 2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0,S = 0,

J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 94: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0,S = 0,

J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 95: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0, S = 0,

J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0,S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 96: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0, S = 0, J = 0

−→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 97: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 98: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 ,

J = 12 −→

2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 99: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2

−→ 2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 100: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 101: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0,

J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 102: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0

−→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 103: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 104: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 ,

J = 12 ,

32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 105: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32

−→ 2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 106: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 107: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0;

J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 108: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1,

2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 109: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2,

2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 110: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0,

1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 111: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1,

1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 112: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1,

0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 113: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→

3D3,3D2,

3D1,1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 114: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 115: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,

3P2,3P1,

3P0,1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 116: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 117: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,

3S1,1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 118: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 119: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

H: (1s)

L = 0, S = 12 , J = 1

2 −→2S1/2

Li: (1s)2(2s)

L = 0, S = 12 , J = 1

2 −→2S1/2

He: (1s)2

L = 0, S = 0, J = 0 −→ 1S0

Be: (1s)2(2s)2

L = 0, S = 0, J = 0 −→ 1S0

B: (1s)2(2s)2(2p)

L = 1, S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 12 / 16

Page 120: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 121: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 122: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 123: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 124: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 125: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 126: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

Page 127: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,

2P3/2,2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,

2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.12(b)

N: (1s)2(2s)2(2p)3

L = 3, 2, 1, 0; S = 32 ,

12 ;

J = 92 ,

72 ,

52 ,

32 ,

72 ,

52 ,

72 ,

52 ,

32 ,

12 ,

52 ,

32 ,

52 ,

32 ,

12 ,

32 ,

12 ,

32 ,

12 −→

4F9/2,4F7/2,

4F5/2,4F3/2,

2F7/2,2F5/2,

4D7/2,4D5/2,

4D3/2,4D1/2,

2D5/2,2D3/2,

4P5/2,4P3/2,

4P1/2,2P3/2,

2P1/2,

4S3/2,2S1/2

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 13 / 16

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Problem 5.13

(a) Hund’s first rule says that, consistent with the Pauli principle, thestate with the highest spin (S) will have the lowest energy. Whatwould this predict in the case of the excited states of helium?

(b) Hund’s second rule says that, for a given spin, the state with thehighest total orbital angular momentum (L), consistent with overallantisymmetrization, will have the lowest energy. Why doesn’t carbonhave L = 2?

(c) Hund’s third rule says that if a subshell (n,l) is no more than halffilled, then J = |L− S | has the lowest energy. use this to resolve theboron ambiguity of problem 5.12(b).

(d) Use Hund’s rules, together with the fact that a symmetric spin statemust go with an antisymmetric position state (and vice versa) toresolve the carbon and nitrogen ambiguities of problem 5.12(b).

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 14 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric.

Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(a) The configuration of the excited state of helium is (1s)1(2s)1

This state can either be the singlet (S = 0) parahelium or the triplet(S = 1) orthohelium.

Hund’s first rule identifies, correctly, that orthohelium will have a lowerenergy than parahelium.

(b) From problem 5.12, we had

C: (1s)2(2s)2(2p)2

L = 2, 1, 0; S = 1, 0; J = 3, 2, 1, 2, 2, 1, 0, 1, 1, 0 −→3D3,

3D2,3D1,

1D2,3P2,

3P1,3P0,

1P1,3S1,

1S0

The first rule forces the highest total spin state, which would be S = 1,which is symmetric. Thus, the spatial function must be antisymmetric andwhile L = 2 is the largest value, it is symmetric and so the ground statemust have L = 1, leaving 3P2,

3P1,3P0 as possibilities

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 15 / 16

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Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

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Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

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Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

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Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 151: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.

The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 152: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 153: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 154: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32

L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 155: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1

= 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 156: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1 = 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 157: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1 = 0

J = L + S = 32

−→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16

Page 158: Today’s Outline - November 30, 2015segre/phys405/15F/lecture_24.pdf · C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 2 / 16. Example: Rolling dice and for 4 dice, 1296 =

Problem 5.13 - solution

(c) For boron, we had the configuration

B: (1s)2(2s)2(2p)

L = 1,S = 12 , J = 1

2 ,32 −→

2P1/2,2P3/2

Since the outermost shell is less than half filled, J = |L− S | = 12 and the

ground state must be 2P1/2

(d) For carbon, we know that S = 1 and L = 1 and sincethe outer shell is less than half-filled, J = |L− S | = 0 sothe ground state must be 3P0.

For nitrogen, let’s use my graphical trick, which main-tains the correct symmetries for spin and spatial states.The configuration of nitrogen is (1s)2(2s)2(2p)3

S = 32 L = −1 + 0 + 1 = 0

J = L + S = 32 −→ 4S3/2

+1

0

2p-1

C. Segre (IIT) PHYS 405 - Fall 2015 November 30, 2015 16 / 16