let me give some remarks on u,v,w vs. fundamental parameters.
Paolo G. Radaelli wrote:
>Modern Lab diffractometers have
>considerably more complex geometries, so it is very well possible that the
>Cagliotti function may not be completely adequate.
Indeed, modern Laboratory X-ray Bragg-Brentano Diffractometers show peak
profiles very different from simple Gaussian. As an explanation, please
have a look on the BGMN site, page
http://www.mineral.tu-freiberg.de/mineralogie/bgmn/ger.html
It becomes clear: Such profiles can only be described by a fundamental
parameters approach. Examples are given on this page.
Armel Le Bail wrote:
>We are waiting for the book "Microstructure Analysis by Diffraction".
>Has somebody some info on the status of this monument, proceeding
>of SIZE-STRAIN'95, Slovakia ?
I took part on the "Size/Strain Round Robin", which was part of this
conference. My software was BGMN, as I know the only Rietveld program
with fundamental parameters research presented on this conference.
And, as I know, BGMN was the only program which was able to detect
the anisotropic strain in the virgilite specimen. All other participants
have presented isotropic or anisotropic size parameters, but never
anisotropic strain. My conclusion was: There was anisotropic strain, size
was nearly isotropic.
This shows the advantages of fundamental parameters for modern Bragg-Brentano
Laboratory X-Ray Diffractometers.
J"org Bergmann
bergmann@rcs.urz.tu-dresden.de