[sdpd] Indexing by HRTEM

[MartinUlrich_Schmidt... @de.clariant.com]

Indexing by electon microscopy: A personal remark

We once had a powder diagram, which could be indexed only with
the help of electron microscopy:
It was an organic specimen, giving a medium-quality powder diagram.
27 of the 30 lines could be indexed  by a=16.24, c=9.23, beta = 99 degree.
The values for b, alpha and gamma remained ambiguous.
By HR-TEM we found not only the missing lattice parameters
(b = 4.8, alpha=gamma=0), but we also detected, that c had to be doubled,
i.e. the lines in the powder diagram corresponded to h0l with l=2n.
Since that time, I prefer to make EM, if indexing is impossible or
ambiguous.