1

Clue to Atomic Structure: Atomic Emission

Clue to Atomic Structure: Atomic Emission

2

Fireworks

Northern Lights

3

electromagnetic radiation

Propagating waves of energy

electric field

magnetic field

: oscillating

Nature of Light

increasing l

increasing

AM

Rad

io

Sh

ort

wave

Tel

evis

ion

FM

Rad

io

Mic

row

ave

Rad

ar

Far

Infr

are

d

Infr

are

d

Ult

ravio

let

X-r

ay

s

gra

ys

1010 1011 1012 1013 1014 1015 1016 1017 1018 1019105 106 107 108 109 s–1

400 nm500 nm600 nm700 nm

visible

10–2 10–3 10–4 10–5 10–6 10–7 10–8 10–9 10–10 10–11103 102 101 1 10–1 m

c = 2.9979 x 108 m/s = speed of light (EM)

; l = cl 1

Electromagnetic Spectrum

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Continuous Spectrum

prism

detector

slit prism

detector

410 nm 434 nm 486 nm 656 nm

high voltage

electric arc

(white light source)

slit

hydrogen gas

Atomic Line Spectra

Line Spectrum

H2He

H

line spectrum

He

line spectrum

Atomic Line Spectra

Li “flame” spectrum

5

He

Na

http://chemistry.bd.psu.edu/jircitano/periodic4.html

Fe

O

Other Atomic Line Spectra

Na HeHeFe Fe

Solar absorption spectrum

n = 4 2 green (486 nm) 3 1 5 3

n = 5 2 blue (434 nm) 4 1 6 3

n = 6 2 violet (410 nm) 5 1 7 3

n = 3 2 red (656 nm) 2 1 4 3UV IR

n = 1

n = 2

n = 3

n = 4

n = 5

n = 6

Balmer series Paschen seriesLyman series

Hydrogen Line Spectrum

Johann Balmer

Swiss

Theodore Lyman

American

Louis Paschen

German

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λ =h

mv

h kg∙m2/s

v velocity, m/s

m mass, kg

light waves behave as particles (hν),

maybe e– particles can behave as waves

e– beam

Au foil

electron

microscope

Louis de Broglie

French

1923

Wave Mechanics

(J∙s)

diffraction

Wave Mechanics

waves quantized!

λ =h

mv

h kg∙m2/s

v velocity, m/s

m mass, kg

e– as standing waves?

light waves behave as particles (hν),

maybe e– particles can behave as waves

Louis de Broglie

French

1923

(J∙s)

7

combined Bohr's atom, deBroglie e– waves and the classical

1-D standing wave equation:

Erwin Schrödinger

Austrian

1925

Schrödinger Wave Equation

?!?!

Y = 0+ + +2Y

x2

2Y

y2

2Y

z2

82m

h2E +

4eor

Ze2

ℓ = 0, mℓ = 0

ℓ = 1, mℓ = –10

+1

–10

+1

ℓ = 2, mℓ = –2

+2

ℓ = 1, mℓ = –10

+1

ℓ = 0, mℓ = 0

n = 1, ℓ = 0,

Orbitals

3px , 3py , 3pz

2px , 2py , 2pz

3dxy , 3dxz , 3dyz ,

3dx2–y2 , 3dz2

1s

2s

3s

n = 1, 2, 3, 4 … ℓ = 0, 1, 2, 3 … (n – 1) mℓ = – ℓ … 0 … +ℓ

1

n = 2,

mℓ = 0

n = 3,

s p d f

(1, 0, 0)

(2, 0, 0)

(3, 0, 0)

(3, 1,–1)

(3, 1, 0)

(3, 1, 1)

(2, 1,–1)

(2, 1, 0)

(2, 1, 1)

(3, 2,–2)

(3, 2,–1)

(3, 2, 0)

(3, 2, 1)

(3, 2, 2)

equations

4

9

8

21/2

81π1/2

Z 5/2

ao

ψ3px , 3py= 6 – re–Zr/3aosinθcosφ

Zr

ao

21/2

81π1/2

Z 5/2

ao

ψ3pz= 6 – re–Zr/3aocosθ

Zr

ao

1

81(3π)1/2

Z 3/2

ao

ψ3s = 2 – 18 + 2 e–Zr/3ao

Zr

ao

Z2r2

ao2

1

4(2π)1/2

Z 5/2

ao

ψ2px , 2py= re–Zr/2aosinθcosφ

1

4(2π)1/2

Z 5/2

ao

ψ2pz= re–Zr/2aocosθ

1

4(2π)1/2

Z 3/2

ao

ψ2s = 2 – e–Zr/2ao

Zr

ao

1

π1/2

Z 3/2

ao

ψ1s = e–Zr/ao

abbreviated n, ℓ, and mℓmathematical functions:

Orbitals

1s

2s

2p

2p

3s

3p

3p mℓ = ±1

mℓ = ±1

mℓ = 0

mℓ = 0

1 Å = 10–10 m

Visualizing Orbitals

1s

2s

3s

r (Å)0

2

4

6

8

10

12

14

0 5 10 15

n = 1

n = 2

n = 33p3d 3s

just n, ℓ

Bohr

0 5 10 15r (Å)

3

2

1

0

rθ

φy

z

x

.

r, θ, φ

polar

coordinates

Radial Plot

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x

y

z

x

y

z

dx2 – y2

y

z

x

x

z

y

dxy dxz dyz

dz2

z

x

y

Angular Plot (θ, φ)

s

z

x

y

x

y

z

px py pz

x

z

y

just ℓ, mℓ

+ or –

Y(x, y, z)

1s 2s 3s 4s 5s 6s

2px 2py 2pz

3pz 4pz 5pz 6pz

Contour Plots: p Orbitals

Contour Plots: s Orbitals

2pz

90%n, ℓ, mℓ

cross section

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3dxy3dyz3dxz

3dx2 – y2 3dz2

Contour Plots: d Orbitals

En

erg

y

1s__

2s__

2p__ __ __

3s__

3p__ __ __

4s__

3d__ __ __ __ __

4p__ __ __

5s__

4d__ __ __ __ __

5p__ __ __

6s__

4f__ __ __ __ __ __ __

Energy Levels of Multi-Electron Atoms

1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s

1 2 3 3 4 4 5 5 5

smallest n; lowest E

sub-orbitals (mℓ) same E

E: n + ℓ

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1s1

3s1

4s1

5s1

6s1

7s1

2s1 2s2

3s2

4s2

5s2

6s2

7s2

4d1

5d1

6d1

3d10

4d2

5d2

6d2

4d3

5d3

6d3

4d4

5d4

6d4

4d5

5d5

6d5

3d1 3d2 3d3 3d4 3d5 3d6

4d6

5d6

6d6

3d7

4d7

5d7

6d7

3d8

4d8

5d8

6d8

3d9

4d9

5d9

6d9

4d10

5d10

6d10

4p1 4p2 4p3 4p4 4p5 4p6

3p1 3p2 3p3 3p4 3p5 3p6

2p1 2p2 2p3 2p4 2p5 2p6

5p1 5p2 5p3 5p4 5p5 5p6

6p1 6p2 6p3 6p4 6p5 6p6

7p1 7p2 7p3 7p4 7p5

4f 1

5f 1

4f 2

5f 2

4f 3

5f 3

4f 4

5f 4

4f 5

5f 5

4f 6

5f 6

4f 7

5f 7

4f 8

5f 8

4f 9

5f 9

4f 10

5f 10

4f 11

5f 11

4f 12

5f 12

4f 13

5f 13

4f 14

5f 14

3d__ __ __ __ __

2p__ __ __

4f__ __ __ __ __ __ __

1s2

1s__

7p6

Valence Electron Configuration

A pattern after Ne:

valence e–

core e–Li 1s 2s

Na 1s 2s 2p 3s

1

s – block (2 columns)

p – block (6 columns)

d – block (10 columns)

f – block (14 columns)

2

3

4

5

6

7

3

4

5

6

2

3

4

5

6

7

4

5

Valence Electron Configuration

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1s22s22p63s23p64s23d104p65s24d10

1s1 1s2

3s1

4s1

5s1

2s1 2s2

3s2

4s2

5s2 4d1

3d10

4d2 4d3 4d4 4d5

3d1 3d2 3d3 3d4 3d5 3d6

4d6

3d7

4d7

3d8

4d8

3d9

4d9 4d10

4p1 4p2 4p3 4p4 4p5 4p6

3p1 3p2 3p3 3p4 3p5 3p6

2p1 2p2 2p3 2p4 2p5 2p6

5p1 5p2 5p3

Complete Electron Configuration

Sb 5p

Sc Ti V Cr Mn Fe Co Ni Cu Zn

Y Pd

Lu Pt

s2d 1

s2d1

s2d 1

s2d 2

Zr

Hf

s2d 2

s2d 2

s2d 3

s1d 4

Nb

Ta

s2d 3

s1d 5

Mo

W

s1d 5

s2d 4

s2d 5

Tc

Re

s2d 5

s2d 5

s2d 6

s1d 7

Ru

Os

s2d 6

s2d 7

s1d 8

Rh

Ir

s2d 7

s2d 8

s0d10

s2d 9

s1d10

Ag

Au

s1d10

s1d10

s2d10

Cd

Hg

s2d10

s2d10

La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb

Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No

d1f 0 d1f 1 d 1f 7

d1f 0 d 2f 0 d1f 2 d1f 3 d1f 4 d 1f 7

f 7f 3 f 4 f 5 f 6 f 9 f 10 f 11 f 12 f 13 f 14

f 6 f 7 f 9 f 10 f 11 f 12 f 13 f 14

Transition Metal Valence Electron Configuration