

Interaction
of identical nuclei equidistant from the centre of the molecule can
produce intensity alternations of sequential spectral lines.
Q4.5 Explain the difference between a Boson and a Fermion
Q4.6 Write down the total wave function of a diatomic molecule, in
terms its constituent wave functions: electronic, rotational and nuclear
spin.
Q4.7 Explain what approximations have been made to get to this result.
Q4.8 What is the behaviour of the total wave function upon by the
exchange of Boson or Fermion nuclei?
If the nuclear spin I = ½, space quantisation of nuclear spin angular
momentum results in the quantum number MI taking values ½ or ½. The
nuclear spin wave function yns is usually written as a and b , corresponding
to MI = ½ or ½. X nuclei, labelled 1 and 2, can have either
or
spin wave functions.
_
= 
_(1)(2)

_(1)(2) 
_(1)(2)

_(1)(2) 
(10) 
