>From what I've read of Cagliotti's paper, the V term should always be >negative; or am I reading it wrong?
Additionally, there is some good work on the use of the Cagliotti (and TCHZ) functions in the paper by Young and Desai; it also goes over how to incorporate sample dependent terms into the expression. Young, R. A. & Desai, P. 1989, 'Crystallite Size and Microstrain Indicators in Rietveld Refinement', Archiwum Nauki o Materialach, vol. 10, no. 1-2, pp. 71-90. Alan Hewat wrote: > .... if you have access to the refinement code. This is why I love Topas. All of the the code used in the refinements is there for you to see! :) Cheers Matthew ________________ Matthew Rowles CSIRO Minerals Box 312 Clayton South, Victoria AUSTRALIA 3169 Ph: +61 3 9545 8892 Fax: +61 3 9562 8919 (site) Email: matthew.row...@csiro.au