January 2004 - Ifeffit - millenia.cars.aps.anl.gov

an artemis question
by Bruce Ravel 06 Jan '04

06 Jan '04

Hi folks, Artemis has a feature which will generate an ifeffit script appropriate to your fitting model without actually running the fit. This feature is found as the second item in the Edit menu. This script can be examined or saved to a file. My question is this: does anyone out there make regular use of this feature? If so, could you please let me know by private email. If anyone does use this feature, I would like to know what the context is in which it is used. Thanks, B -- Bruce Ravel ----------------------------------- ravel(a)phys.washington.edu Code 6134, Building 3, Room 222 Naval Research Laboratory phone: (1) 202 767 5947 Washington DC 20375, USA fax: (1) 202 767 1697 NRL Synchrotron Radiation Consortium (NRL-SRC) Beamlines X11a, X11b, X23b National Synchrotron Light Source Brookhaven National Laboratory, Upton, NY 11973 My homepage: http://feff.phys.washington.edu/~ravel EXAFS software: http://feff.phys.washington.edu/~ravel/software/exafs/

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Using FEFF calc to create "data"?
by sej9＠cornell.edu 06 Jan '04

06 Jan '04

Dear all, Is there any way to create "data" using just a FEFF calculation? I mean, can I use Artemis to create a theoretical EXAFS spectrum from a FEFF calculation without fitting it to any actual data? After seeing my data (from messy environmental soil samples), I came up with another idea for a compound that might be in it (a compound that I hadn't thought of before and so do not have real data from having run it as a model compound), and am trying to figure out the best way to incorporate that new compound into my fit. Thanks, Sarah Johnson

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running feff - a problem
by Tamas Varga 05 Jan '04

05 Jan '04

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maximum argument length?
by Peter Southon 05 Jan '04

05 Jan '04

Hello all, Is there a limit on the total length of arguments that follow an Ifeffit command? If so, is there a way of expanding the limit? I've constructed a rather complicated model which uses 37 paths (mostly multiple scattering). Furthermore, quite a few of these paths are sensitive to scattering angle, so I have calculated FEFF files for three versions each of most paths (each for a different scattering angle), as suggested in the course "EXAFS Analysis with FEFF and FEFFIT" and the old Feffit manual. Thus the final Ifeffit command calls on a lot of FEFF paths, each specifically numbered according to path and angle. Unfortunately, after adding a few extra paths I get error messages when running the feffit command: "feffit:unknown key" followed by a list of paths about halfway through my list, and also "feffit: no chi(k) data array?". I assume that this is because ifeffit will only swallow half the command, which is: feffit(1-4,500,510,520,600,610,620,700,710,720,800,810,820, 9-13,15-16,1700,1710,1720,1800,1810,1820,1900,1910,1920,2000,2010,2020, 37, 3800,3810,3820,3900,3910,3920,4000,4010,4020,4100,4110,4120, 4200,4210,4220,4300,4310,4320,4400,4410,4420,4500,4510,4520, 4600,4610,4620,4700,4710,4720,4800,4810,4820,4900,4910,4920, 5000,5010,5020,5100,5110,5120,5200,5210,5220,5300,5310,5320, 5400,5410,5420,5500,5510,5520, chi = data15.chi, macro = plot_fit) Short of actually renumbering all my paths so that they run sequentially, is there any solution...? Have a merry Christmas, Peter Peter Southon Research Fellow - School of Chemistry University of Sydney, NSW 2006, Australia +61 2 9351 4425

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