Hi Bindu: I am presuming that you mean that you want to tune the bond angle of the MS paths in your EXAFS fitting but, as Bruce notes, I might be wrong. The bond angles for the multiple scattering paths are simply calculated from the positions of the atoms around the central atom in the FEFF input file. In the refinement process used by Ifeffit, the overall path length is slightly changed to fit the experimental data. This implies that a 3-Dimensional geometry has been reduced to a 1-Dimensional fitting and all angular information is locked into the initial FEFF calculation. Thus you can only tune angles by starting with a different local arrangement of atoms around the central atoms. To my knowledge, there is no automatic way of doing this but there are manual ways of approaching the problem depending on the kind of system you are studying. It would be helpful to have more information. Cheers, Carlo On Tue, 27 Nov 2007, Bindu R. wrote:
could you tell me how does one tune the bond angles from the multiple scattreing paths?
Bindu
Dr.Bindu R. Visiting Scientist DCMP&MS Tata Institute of Fundamental Research Homi Bhabha Road Colaba Mumbai-400 005 India Mobile-919892536830
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