On Thu, Mar 18, 2004 at 10:50:28AM -0500, Maxim V. Lobanov wrote:
> > Your sample will probably broaden the lines (LX, LY, etc.) so much that
> > any attempt to vary the Gaussian
> > coefficients will yield nonsense.
> Just some remark (of course, I am not a great specialist):
> At least to my exp
> "Theoretically" U,V,W should not be refined at all as they describe instrumental
> broadening
This is true only when there is no Gaussian strain present.
Brian
"Theoretically" U,V,W should not be refined at all as they describe instrumental
broadening, and this is exactly what I do
(usually). After diffractometer alignment, a good quality pattern in whole possible
angular range has to be collected from "Rietveld
standard" which currently is LaB6. From t
>U, V, and W tend to be highly correlated
The correlation between U,V,W is the result of a resolution curve that doesn't have a
well defined minimum. If you differentiate the Caglioti equation for the FWHM:
FWHM**2=U.tan**2(theta)+V.tan(theta)+W
you obtain the condition for the minimum as
2U.ta
[EMAIL PROTECTED] wrote:
> Please remove me from the mailing list-thank you
I seem to provoke the above response every time I post to the list...
Anyway, to the Inst parm subject, I suggest to GSAS users that they
print out the e-mail message from Bob and staple it to the back of their
well-worn
> Your sample will probably broaden the lines (LX, LY, etc.) so much that
any attempt to vary the Gaussian
>coefficients will yield nonsense.
Just some remark (of course, I am not a great specialist):
At least to my experience, there is always some Gaussian broadening from
the sample as well, and
Donna (and anyone else who wonders about this),
In gsas\examples there is an iparm file (inst_xry.prm) that can be used for most any
Bragg-Brentano powder diffractometer. These instruments all perform more or less
equally independent of manufacturer with respect to the things of interest for
Rie
Hi!
I am trying to refine some XRD data using GSAS and looking for an
instrument parameter file for the Rigaku Dmax 2000 x-ray diffractometer.
Can anyone help?
Thanks Donna
