One other reference worth noting is Ted Prince's paper in J. Appl. Cryst
[p508-511 (1983). "THE EFFECT OF FINITE DETECTOR SLIT HEIGHT ON PEAK
POSITIONS AND SHAPES IN POWDER DIFFRACTION"]. Ted has a single-parameter
asymmetry model that is computationally simpler than the
Finger-Cox-Jephcoat (thoug
Laboratorio MDM - INFM
Two-Years Post-Doctoral Position in diffraction/reflectivity from thin
films.
In the frame of a european project
Laboratorio MDM-INFM in the frame of the European Project ESQUI
http://pecdc.univ-lemans.fr/esqui/esqui.htm is offering a post-doctoral
two-years position in X-r
>Does anyone know of a good reference which discusses peak asymmetry in
>low angle X-ray powder diffraction data?
Bruce,
Such peaks characterize many XRD tracings of clay minerals. I suggest
looking first at Reynolds 1989, Diffraction by small and disordered
crystals. In Bish, D.L., and Post, J.E
I realise that this is not strictly a Rietveld question but I thought
that
subcribers to this list may the best audience to answer it.
I'm looking for suggestions for softaware that will calculate the
reference intensity ratio (RIR) of phases with some flexibility to chose
peak areas or heights
I came across this problem in Feb 1998. Following is a
response from Bob on how to get around this. (to save
on a repeat) Seems to be some wierdness in IRIX 6.5
Lachlan.
>This one looks familiar. Look at the section "case expnam:" in the gsas
>shell. There is a line that reads:
>
>set inpl
Some of the references noted in the following webpage might
help:
http://www.ccp14.ac.uk/maths/index.html#funpar
This deals with Fundamental Parameters and ray tracing
methods such as from Bergmann et al and Cheary and Coelho.
Included are some links to images which show these
algorithms in
Asymmetry is discussed in:
J.Appl.Cryst (1984) 17, p.47 - van Laar & Yelon (+ ref's therein)
The above method is implemented in:
J.Appl.Cryst (1994) 27, p.892 - Finger, Cox & Jephcoat.
and source code for this peakshape is available. (They also talk about
secondary monochromators).
Hope th
Does anyone know of a good reference which discusses peak asymmetry in
low angle X-ray powder diffraction data?
--
Bruce A. Weir,
Optoelectronics,
Cavendish Laboratory,
University Of Cambridge,
Madingley Rd,
Cambridge,
