Stefan: The recent paper (Journal of Applied Crystallography 37 (2004) 911-924) gives several recommendations and recipes for extracting size/strain results, using Rietveld refinement, in particular GSAS. The reprint can be downloaded from http://www.du.edu/~balzar/
Good luck, Davor > -----Original Message----- > From: Stefan Berger [mailto:[EMAIL PROTECTED] > Sent: Friday, June 30, 2006 7:47 AM > To: rietveld_l@ill.fr > Subject: AW: RE: Crystal size in GSAS > > is FWHM in GSAS given in rad or degree? And how i convert > FWHM in integral breadth, with following formulas? > > Gauss: > ß=fwhm*pi/2 > > Lorenz > ß=((pi/ln2)^0.5)*fwhm)/2 > > and from GSAS manual > > ß=((8*ln2)*fhwm^2)^0.5 > > which i have to use? > > Stefan > > > ______________________________________________________________ > ______________ > Stefan Berger > INNOVENT e.V. > Technologieentwicklung Jena > Abteilung Biomaterialien > Prüssingstraße 27b > 07745 Jena > Tel. +49 3641 2825 - 43 / -20 > <<mailto:[EMAIL PROTECTED]>> > ______________________________________________________________ > ______________ > > > > -----Ursprüngliche Nachricht----- > Von: Whitfield, Pamela [mailto:[EMAIL PROTECTED] > Gesendet: Freitag, 30. Juni 2006 15:26 > An: rietveld_l@ill.fr > Betreff: RE: Crystal size in GSAS > > > Stephane > > Just one small point - strictly speaking you should be using > integral breadth rather than FWHM for size/strain analysis. > > Pam > > -----Original Message----- > From: Von Dreele, Robert B. [mailto:[EMAIL PROTECTED] > Sent: June 29, 2006 2:24 PM > To: rietveld_l@ill.fr > > > Stephanie, > The GSAS routine REFLIST has an option to produce a "single > phase ascii" file of reflections. One of the columns in that > file is FWHM. Alternatively there is a graphic in EXPGUI > (widplt) that will plot FWHM and its Gaussian & Lorentzian > contributions as a function of 2-theta. Bob Von Dreele > > R.B. Von Dreele > IPNS Division > Argonne National Laboratory > Argonne, IL 60439-4814 > > > > -----Original Message----- > From: ruggeri [mailto:[EMAIL PROTECTED] > Sent: Thursday, June 29, 2006 12:17 PM > To: rietveld_l@ill.fr > > > Hello, > I am trying also to calculate crystal size from GSAS, and I > want to find back the fwhm of all the peaks from their > position: how is it possible? Thanks > > Stéphane Ruggeri, Ph.D. > Stagiaire post-doctoral > INRS Énergie, Matériaux et Télécommunications > 1650, boul. Lionel-Boulet > Varennes (Québec) > J3X 1S2 > Téléphone/Office : (450) 929 8139 > Télécopieur/Fax : (450) 929-8198 > > -----Message d'origine----- > De : [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > Envoyé : 29 juin 2006 13:31 > À : rietveld_l@ill.fr > Objet : Crystal size in GSAS > > > Hi, > > I am wondering if GSAS calculates the crystal size? If not > how can I calculate the crystal size? I am using a profile > type 3 function (psedo > voight) and obtaining the GU,GV,GW values as 0,0, 1.27 E+04 > for a Pt/C phase respectively. The Chi-square fit is 2.164. > Thankyou. > > regards, > > Sajeev Moorthiyedath > > > >
