Reading in Levine: Chapter 20
Homework problems
Hand in on Wednesday, April 22: In class problem on low resolution rotational contours
Hand in on Monday, April 27: 20.43, 20.49, 20.50,20.97, 20.98, 20.103, 20.122, 20.125
Key Concepts
Permutation symmetry of nuclei in homonuclear diatomic molecules
Nuclear spin statistics (see handout)
In the electronic state term symbol for a diatomic:
, +/- refers to symmetry of the electronic wavefunction with respect to a mirror plane containing the diatomic axis; g/u is relevant only for homonuclear diatomics and refers to the even/odd symmetry under inversion of coordinates. g comes from the German word for even --gerade--and u from ungerade. The left superscript is the multiplicity (2S+1) as for atoms.
Rotational band contours for heavy diatomics at low resolution.
Rotations of polyatomic molecules
Polyatomic vibrations group theory (see handout)