Dear João
I have read J. I. Langford's article (J. Appl. Cryst. 2000. 33, 964-974 ) and there I saw the following equation for the line profile (that was obtained from A.J.C. Wilson-1962): I(2theta) = [cos(theta)/lambda] I(s) I would like to know what the exact meaning of the cos(theta) factor in this equation is. What does it describe? I will be very grateful for some help.
the term just account for the passage (done in the formula) from reciprocal space to 2theta space. Easy to demonstrate:
s = 2 Sin[theta]/lambda so, taking the differential (for fixed lambda) ds = 2 Cos[theta]/lambda dtheta = Cos[theta]/lambda d(2theta) Enjoy M -- ------------------------------------------------------------ Matteo Leoni, PhD Department of Materials Engineering and Industrial Technologies University of Trento 38050 Mesiano (TN) Italy Tel +39 0461 882416 e-mail: [EMAIL PROTECTED] Fax +39 0461 881977 Web: www.matteoleoni.ing.unitn.it ------------------------------------------------------------
