At 05:19 23/09/2004 -0700, you wrote: >Dear All, > >I have a compound with apatite structure. There are 3 cations La, Bi and Ba. I need to fix them in either of two sites (6h and 4f) available. I am trying with different combinations of these atoms in the two sites. Still I am not getting the correct fit in the sense the final composition after refining occupancy is not matching with the formula. I think the absorption correction has to be incorporated to overcome this problem. I am using FullProf-2000 version. How to give the absorption correction in the refinement? Can anyone suggest me a solution to this problem? > >Sincerely, >Lakshminarasimhan. >
Are you using x-ray or neutron diffraction? If x-ray, the scattering factors for La and Ba are pretty much identical. If neutron, the La and Bi are very similar. Refining such occupancies together should thus be done with great care. What is the rest of your sample? jools ----------------------------------------------------------------------- Dr. Julian Tolchard Email: [EMAIL PROTECTED] Cecil Davis Lab Chemistry (C4) Tel: +44 (0)1483 689591 University of Surrey Guildford, GU2 7XH -----------------------------------------------------------------------
