To all: What is the correct procedure for refining U,V,W? It is my understanding that those parameters are a function of instrument geometry. Does one use a standard material to determine U,V,W and then fix their values for the instrument you're using?....or do the values of U,V,W change depending on the sample being examined? If so, why do the values change? Thanks in advance. Frank May
________________________________ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Sun 11/30/2008 1:32 PM To: rietveld_l@ill.fr Subject: Re: I am a newcome, how can I begin my rietveld refinement analysis Hi, Li: To me, the most wonderful tool to determine initial peakshape parameters is CMPR. CMPR is especially oriented to GSAS and gives you GU, GV, GW etc. And when you use EXPGUI for GSAS, you can also try Graphs->widplt to see how FWHM develops when parameters are tuned. When you prefer Fullprof, you should take a factor to get U, V, W etc. i am not sure about the facor exactly, maybe GX~100X(X=U, V, W), er..? Anyway, just go ahead and make a try. Faithfully Jun Lu ---------- Lst. Prof. Lijie Qiao Department of Materials Physics and Chemistry University of Science and Technology Beijing 100083 Beijing P.R. China http://www.instrument.com.cn/ilog/handsomeland/
