2.3 Ammonia Molecule, as Example of Tetratomic
Molecule
We assume the following base of atomic orbitals u 1 ¼ 2s N u 2 ¼ 2p x u 3 ¼ 2p y
u 4 ¼ 2p z u 5 ¼ 1s ðH 5 Þ u 6 ¼ 1s ðH 6 Þ u 7 ¼ 1s ðH 7 Þ (Scheme 2.6).
Referring to C 3v symmetry, the characters of the reducible representation under
the related symmetry operations are
E 2C 3 3r v
7 1
3
1b 2
2000
1800
1800
1400
1200
1a 1
1b 1
Fig. 2.1 Photoelectron spectrum of water, indicating the electronic transitions
Scheme 2.6 NH 3 molecule
2.3 Ammonia Molecule, as Example of Tetratomic Molecule
33