Dear all,
I have some questions concerning the refinement
of the gppd data and would appreciate your advice:
1) The patterns show some kind of texture(up
and down on the error curve), but the sample is powder(although maybe the
granules are large) and should be isotropic. All banks show this
characteristic texture behavior.
2) For different banks, the sign of error for
the same (hkl) gradually reverse, and it's hard to refine.
3) If UISO factors are let free, the refinement
will go bad, even if they are constrained.
4) For one series of sample, the peaks are
really sharp, the error sign is always like -/+/-, the positive error is
very big and sharp.
5) There are some small peaks, which may be due
to martensitic transformation. But they are really small, i don't know to
what degree i should trust these data. Somebody said maybe that's due to
contamination. If it is martensitic trans., how can i set a proper model to
refine the data?
Sincerely,
Ling Yang
PhD student in Dr. Wang's
group
701 Scarboro Rd
Oak Ridge, TN 37830
Tel: 865 574 0337
Fax:
865 241 5177
