Dear all,
I am not sure I understand point groups and relations between groups and
subgroups anymore, and would appreciate some guidance.
I was under the impression that all point groups were related to an
original P1 cell, and that by applying specific lattice symmetries, one
could "get" higher point groups. Thus, if one knows the symmetry
operators, one could jump from one point group to another. Inspection of
the reflections can then determine the "real" point group and space group.
At least that's what I thought Mosflm was doing? Am I correct?
P1 +(symm-opp)>C2 + (symm-opp2)>P3
same P1 +(symm-opp3)> P2 + (symm-opp4)>P222 ....
If that's the case, could someone point to me where to find these
symmetry opperators (International tables?), because it's not obvious to
me.
Or are these relations between groups and subgroups only true for
certain crystals where the cell parameters are specific, and allows a
symmetry operator to generate a higher symmetry point group?
Thank you for your help.
vincent
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