On Friday 07 September 2007, Saraiya, Neeraj M. wrote:

Hi Bruce, I am somewhat of a first time user of the Ifeffit software package and had a question regarding the Atoms package. I am trying to input x,y,z coordinates for a crystal structure and I realized that the coordinates are the same for two different elements - i.e. two elements that can interchange with each other in the structure. How can I account for the differing ratios of occupancy between the two elements? Thanks in advance for addressing this question.

Best, Neeraj

Neeraj, This is a common question, so I am taking the liberty of CCing my answer to the mailing list. Look at the last question ("How do I handle doped materials? Why doesn't Atoms handle doped materials?") on this FAQ page: http://cars9.uchicago.edu/iffwiki/FAQ/FeffitModeling If you still have questions after reading that, go ahead and post your questions on the mailing list and we'll see what we can do about answering them. B -- Bruce Ravel ---------------------------------------------- bravel@anl.gov Molecular Environmental Science Group, Building 203, Room E-165 MRCAT, Sector 10, Advanced Photon Source, Building 433, Room B007 Argonne National Laboratory phone and voice mail: (1) 630 252 5033 Argonne IL 60439, USA fax: (1) 630 252 9793 My homepage: http://cars9.uchicago.edu/~ravel EXAFS software: http://cars9.uchicago.edu/~ravel/software/