Introduction into the |
Science and Fun Spectroscopic Tools |
Step: 123
There is the symmetry elements: S 2n , C 2 , s h, s v.
There are theoretically n values l, 2, 3..., 
to assume, arises the multiplicity of the point groups can. (contrary
to conditions with molecules crystals cannot assume n any more all values
of n). For reasons of the space fulfilment only the cases n = l, 2, 3,
4, 6 occur. Therefore there are only 32 point groups, those with crystals
the 32 crystal classes corresponds.)
Note the fact that n in each concrete molecule evenly even is given to
the appropriate axis of rotation by the value of n (e.g. for NH
3 is considered as group of points of C 3v , because
n is equal to 3).
It continues to go with
training step 124 !