Hello,
About influence of misalignement on peak assymetry; A good mean to improve
symetry of peaks at low angles is to use soller slits, indeed other
parameters than alignement can be responsible for asymetry.
As for modeling peak shape, I use Fullprof and i also have difficulties to
find a good
For the original query - what about doing a Le Bail fit
to get the best profile fit without being biased by the
structure. Then lock the profile and refine on the structural
parameters? This might be a little tricky with GSAS as I
don't believe it recycles the HKL file like Fullprof does.
But w
Dear Colin,
I am following with interest the discussion you started on the modeling of
low angle XRD peaks. I, too, have had difficulty modeling data with our
inhouse Philips diffractometer (even with function #3 as suggested to me by
Bob von Dreele) and have begun to question Philips directly ab
Colin,
While I do not have very much experience using the Finger-Cox-Jephcoat
model on lab diffractometer data, I can say that it works at least
pretty well on every problem I have tried and usually does OK when the
S/L and H/L values are set at the values matching the instrument design
and are
>
>I presume that you want to use Pearson VII to fit low angle profiles
>as those peaks are assymetric. It sounds like you have significant axial
>divergence. Have you tried Jephcoat,Finger, Cox modification to
>Pseudo-voight (profile function 3 in GSAS)? It usually dose a very good job
At 07:05 PM 2/1/99 +0100, you wrote:
>
>
>Dear All,
>
>I have a diffraction profile which spans 5-160 degrees. My problem is
>getting an adequate fit for four or five peaks which lie in the range 7-20
>degrees. I have split my data into two histograms (5-20 and 20-160 deg) to
>try and alleviate
Dear All,
I have a diffraction profile which spans 5-160 degrees. My problem is
getting an adequate fit for four or five peaks which lie in the range 7-20
degrees. I have split my data into two histograms (5-20 and 20-160 deg) to
try and alleviate the problem, and although the fit is better i
