Hi all, Thanks, Mike, I'd never tried that option before. But I agree with Carlo that it's not that easy a way out, since you still have to understand how to assign potentials in a FEFF.INP file...exactly the sort of thing the Artemis front-end is supposed to protect newbies from, I think. A question for Carlo--I guess I'm not clear on what the impact is of tetrahedral vs. octahedral or whatever if all you're doing is a single-scattering nearest-neighbor EXAFS analysis. Isn't a symmetric octahedral arrangment just the single-scattering path with a degeneracy of 6; a tetrahedral a degeneracy of 4; etc.? Why have FEFF calculate anything other than the single-scattering path? Having said that, I could see an option that lets you generate a single FEFF path via the Artemis front end (and maybe even specify a degeneracy up front). That way you wouldn't have to deal with any of the rigamarole of choosing a low-symmetry space group and putting your atoms somewhere appropriate in the unit cell. It would certainly make things easier for me on occasion (sometimes I have an amorphous component mixed in with the crystalline stuff, for example). The one thing that makes me nervous about this is that I almost don't want to make single-shell single-scattering fits =too= easy for novice users. I work with a lot of undergraduates, and in my experience it's hard for people new to EXAFS and characterization in general to understand just how unreliable such fits can occasionally be, due to high correlations between fitted parameters, leakage from higher-R shells, issues with the background, etc.. A fit with more shells and/or multiple scattering is more likely to =obviously= fail (e.g. yield a poor match between fit and data) if something is wrong. So I guess I kind of like there to be a little bit of a learning process new people have to go through before they can make Artemis do anything, so that they least understand that there can be paths beyond the first. :) But this is really just a gut feeling--it's possible that a single path shortcut like Carlo describes will just make the learning curve easier... --Scott Calvin Sarah Lawrence College