On 08/08/2016 11:19 AM, Carlos Triana Estupinan wrote:

I want to know if it is possible to obtain a 3D structure (.cif file) of an amorphous material from the EXAFS fitting carried out from artemis. I mean, there is a way to extract a .cif file with the structural data obtained from the refined spectra.

No. EXAFS is basically a one-dimensional measurement. You measure R. Multiple scattering gives you limited information about the 3D arrangement of atoms, but mostly EXAFS is just R. Unless I am misunderstanding the question, I don't think you can do what you are asking even for a well-ordered crystal, much less an amorphous material.

Also, in amorphous materials there must be a distribution of interatomic bond distances and coordination, and so, how can I address such a structural distribitions.

Well, sure. There is a while literature on the use X-ray or neutron scattering along with EXAFS and molecular dynamics and monte carlo methods to study amorphous materials. It seems that the most successful approaches involve forward modeling -- i.e. testing structures against the EXAFS data. There simply isn't enough information in EXAFS to invert the EXAFS and extract a 3d configuration. Artemis does not even try to do that. B -- Bruce Ravel ------------------------------------ bravel@bnl.gov National Institute of Standards and Technology Synchrotron Science Group at NSLS-II Building 743, Room 114 Upton NY, 11973 Homepage: http://bruceravel.github.io/home/ Software: https://github.com/bruceravel Demeter: http://bruceravel.github.io/demeter/