Dear Ifeffit users, I am working on EXAFS analysis of a mineral Arrojadite. It has very very complicated crystal structure. I have measured EXAFS in fluoresence mode on Mn and Fe edge. The mineral contains Mn and Fe as divalent cations distributed over 7 different atomic positions e.g. 3 different Mn atomic position (Mn1, Mn2 and Mn3) and 4 different Fe position (Fe4, Fe5, Fe6, Fe7). My question is : How do i know that How many paths should i take into consideration to fit 1st shell, 2nd shell and 3rd shell.. ?? I have rough idea that the first shell is octahedral Oxygen ions. I tried fitting first shell taking into account first 6 Oxygen paths and it gave reasonably good fit to first shell. But the confusion is how to consider paths for 2nd Shell, 3rd shell....etc. Your feedback is highly appreciated. P.S. I have attached artemis file (both Fe and Mn edge) with this mail for your reference. Best regards, Jatin