eÐl620m / life in the universe life in the universe astrophysics – chemistry – biology –...
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EÐL620M / Life in the Universe
Astrophysics – chemistry – Biology – earth-/planetary sciences
•Atoms - chemical bond
•Carbon chemical bond
•Atoms and molecules in space; Informations derived from spectroscopy
•Molecules in the universe;Existance and formation
•Interactions between light and matter ;photochemistry, photoionization, photofragmentation
•Thermochemistry in the Universe•Biochemistry
Atom:
nuclei: p, +n, 0
electron: e-
0.1 nm
0.1 10-9 m10-10 m
?
?
?No wave(?)No electron(?)
?
Standing waveElectron in an orbit
Energy
n=1
n=2
n=3
n :
0
-
2n
RE
but, Three dimension ?
2(r)
r
Þ.e. líkindasvæði 2(x,y,z)
n....... n+1 ....... n+2 ........
n
S - svigrúm
2(r,)
r
2 e- per
orbital
- Opposite spins:
E
n = 1
n = 2
n = 3
:n = 4
l = 0/s l = 1/p l = 2/d l = 3/f
::
::
::
.1x e-
H.
H: 1s1; ground state
H*: > 1s1; excited states
R2
r
Na: 1s22s22p6 3s
Na+: 1s22s22p6
screening:
3s
Na*: 1s22s22p6 3p
3p
Na**: 1s22s22p6 3d
3d
E
n = 1
n = 2
n = 3
:n = 4
l = 0/s l = 1/p l = 2/d l = 3/f
::
::
::
.
A > H.
e.g. C(6e-)
C: 1s2,2s2,2p2
C*, e.g. : 1s2,2s2,2p13s1
E
n = 1
n = 2
n = 3
:n = 4
l = 0/s l = 1/p l = 2/d l = 3/f
::
::
::
.
A > H.
e.g. C(6e-)
Relationship between atoms and valence electron orbitals
H H
21s 2
1s
1s + 1s)2
1s - 1s)2
2 x 2e-2 x 2e-
2 x atom orbitals 2 x molecular orbitals
1s + 1s)2
1s - 1s)2
+
--
-
- --
-
-
+
attractionr-forces, F-
attraction-forces, F-
repulsion-forces, F+
attraction-forces, F-
repulsion-forces, F+
netRepulsion forces:
antibonding
NetAttraction forces:
bonding:
Chemical bond
--
--+ +
2x
::
2x
2xn = 1
n = 2
n = 3
::
E::
::
::
n = 1
n = 2
n = 3
::
Es
Molecular energies (orbitals) quantized
A, AB ...... Low energy electron configurations /Ground states
A*, AB*...... High energy electron configurations/ excited states
NB!