Dear all, I came up with a question about the magnetic form factor of Dy3+ ion. If I calculate it using seven coefficients (A,a,B,b,C,c,D) contained in a internal table of FullProf with a label JDY3, I get a value larger than 1 at x=sin(theta)/lambda=0. To my (little) knowledge, magnetic form factors should be 1 at x=0 because j0(0)=1 and j2(0)=0. I have compared the magnetic form factor of Dy3+ with the one calculated from the coefficient sets in International Tables for Crystallography (2006). Vol. C, Section 4.4.5 with a formula j0+gL/g*j2, and I got a scaling factor 1.132 between the two curves.
For the case of Nd3+, it is confirmed that coefficient sets of JND3 and ITC give almost same values. Here is a link for a picture which summarizes my question. https://www.dropbox.com/s/8zgqdeqymbk4qla/magnetic_form_factor_of_Dy_Nd.png Note that JDY3 curve(blue) and scaled ITC curve(light blue) does not agree well in high Q range. This also puzzles me. Do you have any ideas? By the way, is there any way to look into the internal table of form factors in FullProf? I know that I can find seven-coefficients sets used in a calculation in .out file but I would like to make a list of the coefficient sets available in FullProf. Thanks in advance. Best, Kotaro //================//================// Kotaro SAITO High Energy Accelerator Research Organization Institute of Materials Structure Science 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan //================//================//
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