Dear Dr. Newville, Thank you so much for your reply. Things are very much clear now. With best regards, Jatin ________________________________________ From: ifeffit-bounces@millenia.cars.aps.anl.gov [ifeffit-bounces@millenia.cars.aps.anl.gov] on behalf of ifeffit-request@millenia.cars.aps.anl.gov [ifeffit-request@millenia.cars.aps.anl.gov] Sent: Thursday, April 05, 2012 7:00 PM To: ifeffit@millenia.cars.aps.anl.gov Subject: Ifeffit Digest, Vol 110, Issue 6 Send Ifeffit mailing list submissions to ifeffit@millenia.cars.aps.anl.gov To subscribe or unsubscribe via the World Wide Web, visit http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit or, via email, send a message with subject or body 'help' to ifeffit-request@millenia.cars.aps.anl.gov You can reach the person managing the list at ifeffit-owner@millenia.cars.aps.anl.gov When replying, please edit your Subject line so it is more specific than "Re: Contents of Ifeffit digest..." Today's Topics: 1. Re: Theoretical value of S02 for different absorber (Rana, Jatinkumar Kantilal) 2. Results Reporting (John Farell) 3. Re: Results Reporting (Bruce Ravel) 4. Re: Theoretical value of S02 for different absorber (Matt Newville) ---------------------------------------------------------------------- Message: 1 Date: Thu, 5 Apr 2012 10:44:05 +0000 From: "Rana, Jatinkumar Kantilal" To: "ifeffit@millenia.cars.aps.anl.gov" Subject: Re: [Ifeffit] Theoretical value of S02 for different absorber Message-ID: <6FCB59A6A97E13429B863B7014B57E4B10E2E8@didag1> Content-Type: text/plain; charset="utf-8" Dear Dr. Ravel, Thank you very much for your prompt reply. I followed the instruction on (http://leonardo.phys.washington.edu/feff/wiki/index.php?title=EXAFS_calculat...) and activated S02 card by making S02 0.0 in feff.inp file. As a result, FEFF calculated S02. However, I get confused when I compare FEFF calculated S02 with reported value in literature and the one obtained from my own fit. For example, S02 for Mn absorber FEFF calculated 0.94 Fitted value for my sample ~0.75 Fitted value for various Mn-oxides ~0.75 Other reported value from Mn fit ~0.70-0.80 (http://www.sciencedirect.com/science/article/pii/S0020169397057496) S02 for Fe absorber FEFF calculated ~0.94 Fitted value for Fe-foil ~0.70 Fitted value for various Fe-oxides ~0.70 Reported value by calculation 0.69 (http://prola.aps.org/abstract/PR/v169/i1/p27_1) It is well known that S02 is a property of central absorbing atom and is considered to be constant between 0.7 - 1.0. However, in real world, S02 is affected by various systematic errors like thicker samples (in transmission), absorption by other elements in sample at given energy range and many more. These factors can suppress the amplitudes of EXAFS oscillations resulting in lower value of fitted S02 than it should be for a given absorber. The reason I am so much curious about S02 is, if I know what should be (or should be considered) the value of S02 for a given absorber than I can possibly understand the reasons of fitted S02 being too low or too high. For instance, S02 and Sigma2 are highly correlated for first shell. So from fitted value of S02 and Sigma2 of first shell, I could possibly understand changes in local structure. So I would like to put forward very simple but still confusing question that which value of S02 should be considered, FEFF calculated or the one obtained by fitting standards (either reference foils or reference compounds measured on same beamline) and why. Many thanks in advance !!! With best regards, Jatin -----Original Message----- From: ifeffit-bounces@millenia.cars.aps.anl.gov [mailto:ifeffit-bounces@millenia.cars.aps.anl.gov] On Behalf Of ifeffit-request@millenia.cars.aps.anl.gov Sent: Mittwoch, 4. April 2012 19:00 To: ifeffit@millenia.cars.aps.anl.gov Subject: Ifeffit Digest, Vol 110, Issue 5 Send Ifeffit mailing list submissions to ifeffit@millenia.cars.aps.anl.gov To subscribe or unsubscribe via the World Wide Web, visit http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit or, via email, send a message with subject or body 'help' to ifeffit-request@millenia.cars.aps.anl.gov You can reach the person managing the list at ifeffit-owner@millenia.cars.aps.anl.gov When replying, please edit your Subject line so it is more specific than "Re: Contents of Ifeffit digest..." Today's Topics: 1. Theoretical value of S02 for different absorber (Jatin Rana) 2. Re: Theoretical value of S02 for different absorber (Bruce Ravel) ---------------------------------------------------------------------- Message: 1 Date: Wed, 4 Apr 2012 17:45:13 +0800 (SGT) From: Jatin Rana To: "ifeffit@millenia.cars.aps.anl.gov" Subject: [Ifeffit] Theoretical value of S02 for different absorber Message-ID: <1333532713.14873.YahooMailNeo@web193501.mail.sg3.yahoo.com> Content-Type: text/plain; charset="utf-8" Dear Ifeffit users, Can anyone recommend a reference where I can get calculated value of S02 for various elements ? I would like to compare them with my fitted values. Many thanks in advance !! With best regards, Jatin Rana