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Re: [sdpd] Thermal parameters

I am not sure if this is helpful but the article in wikipedia
http://en.wikipedia.org/wiki/Debye%E2%80%93Waller_factor
defines the thermal parameter as describing the attenuation of x-ray
scattering caused by thermal motion. So basically the bigger the B the more
attenuation (or the wider the diffraction peak) BUT if you don't know what
you are doing and blindly refine you can get negative B or other non real
solutions.

Basically most text books on x-ray diffraction have some sections on this
under B factors , thermal parameters or Debye Waller.

You ask what paraters are effected by B - Well in my opinion problems with
incorrect choises of B in Rietveld refinement for determining the analysis
of a mixture are highlighted in an excellant paper
O?Connor, B., and Li, D. Influence of Refinement Strategies on Rietveld
Phase Composition Determinations. Advances in X-ray Analysis, Vol.42, p.
204-211. in
http://www.icdd.com/resources/axa/vol42/V42_22.pdf

Again in my opionion if you must know what you are refining in Reitveld.

I hope that this is of some use
<http://en.wikipedia.org/wiki/Debye%E2%80%93Waller_factor#cite_note-Debye1913-0>

>
> Hi,
> Can any one please explain what the "thermal parameter" in rietveld means
> and its physical significance...?
> What are the parameters that are affected by this B?
> Suhas Desai
>
> Laurie Aldridge


[Non-text portions of this message have been removed]



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