[Ifeffit] idealized 95-atom Pt clusterCharles, The 95 atoms Pt cluster you describe sounds strange. It does not fit any sequence of magic numbers typical for regular polyhedral clusters (13, 55, 147... for cuboctahedral fcc and icosahedral clusters, or 13, 38, 79, 140... for truncated octahedral or : 10, 37, 92, 185...for supported cuboctahedral clusters). If you are modeling an fcc cluster (Pt does pack into fcc structure, even for sizes smaller than your clusters, contrary, e.g., to Au which is possible to observer in icosahedral structure for 13-atom clusters) then your "spherical" cluster of 95 atoms is not a closed shell cluster and thus it is not a stable isomer. What are you trying to accomplish? Anatoly Anatoly Frenkel -----Original Message----- From: ifeffit-bounces@millenia.cars.aps.anl.gov [mailto:ifeffit-bounces@millenia.cars.aps.anl.gov]On Behalf Of Charles Chusuei Sent: Monday, May 16, 2005 4:48 PM To: ifeffit@millenia.cars.aps.anl.gov Subject: [Ifeffit] idealized 95-atom Pt cluster Hi,,, I'm a new user to Artemis and Atoms. I would like to generate a simulated EXAFS spectrum of an idealized bare 95-atom cluster of Pt (with no ligands attached to it). Looking at Cambridge data files, the largest cluster documented is 18, so I would have to make one up. I would like to arrange the 95 atoms into an idealized sphere with the standard geometry for bulk Pt-Pt bonding that can be predicted from the crystal structure (e.g. metallic radius = 139nm, metallic separation = 277.5nm separation, etc.) I understand this can be done using Artemis and Atoms. I'm relatively new to using the software (prodominantly know how to use Athena for plotting the experimental EXAFS data , not much more). Could anyone provide suggestions on how to get started on this task? E.g. Generating the crystal data and displaying the EXAFS of the resulting bare cluster? Charles _______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit