Dear All Dear I have EXAFS spectra for spinel Co3O4, and I have to determine the inversion degree X, or the cation distribution of Co at the octaedral and tetraedrical sites. The EXAFS fitting can be performed employing two clusters of atoms, one having the absorbing atom in tetrahedral site and one having the absorbing atom in octahedral site. However, I do not know how to exactly determine the fraction of cations in octahedral or tetraedral sites from fitting the spectra with two sites independently. Could you please tell me how exactly should I proced, can I define a EXAFS fitting parameter giving me the cation distribution of Co at the octaedral and tetraedrical sites. If so, how can I do it. Thanks and best regards, -- *Carlos Augusto Triana Estupiñan* * M.Sc. Sciences - **Physics* *Physicist* * Tel: +57 322 256-2309*