[Ifeffit] *****SPAM*****Creating EXAFS coefficient file for reverse monte carlo simulation

Hello everyone, I have synchrotron XRD and XAFS(L3 Tb edge) data on Al90Tb10 metallic glass alloy that i want to use them as constraints in a reverse monte carlo simulation(RMC_POT). RMC_POT manual says i need 2 files for XAFS. 1st chi(k)-k file which i exported from athena as normalized data and 2nd exafs coefficient file which i don't understand what it is or how to create it. I was wondering if anyone can help me on how to create this file or point me on a direction to get more info on this? Best wishes, Tolga Han Ulucan