Hi Bob,
The band of delt/sig is a little wider than that, but I think the real problem is that they sent me the data in cps. I am awaiting the data in counts now. Thanks to you and others for pointing this out. However, in my view, having the data in cps should simply go into the histogram scale factor and should not affect the fit. What is wrong with my logic? Thanks, - Kurt -----Original Message----- From: Von Dreele, Robert B. [mailto:[EMAIL PROTECTED] Sent: Friday, February 15, 2008 6:37 AM To: rietveld_l@ill.fr Subject: RE: advice on new powder diffractometer Hi Kurt, If you plot the results in POWPLOT & do the "statistical analysis" what does the delt/sig vs 2-theta plot look like? If weights are right then the band of delt/sig ought to be roughly 2-3 sig wide. Is your data in cpm? Some instruments make that by default. That will mess up the R-factors. Bob