Hi Elsa: As Matt suggested, you want to change E0 in Athena to produce a new chi(k) spectrum. You can read the theoretical chi(k) spectrum that you made with E0=0 into Athena, adjust E0 for the measurement, and then plot in k the data and theory to see them match at low k.
I encourage you to poke around at the project files that I put at www.xafs.org/ShellyKelly. These project files show how to reproduce the relevant figures in the book chapter. Good luck, Shelly On Thu, Sep 30, 2010 at 10:33 AM, Elsa Sileo <e_si...@yahoo.es> wrote: > Dear Matt, > > I have to perform EXAFS analysis, and when I tried to fit the first shell, > I found deltaE0 values of about 8 eV. Following the paper of Kelly et al > (Analysis of soils and minerals using X-ray absorption spectroscopy. In > Methods of soil analysis, Part 5: Mineralogical methods; 2008; pp 446) > I fitted the first shell obtaining values for deltaE0, sigma^2; delta R > and amplitude. Then, using the obtained values, and making deltaE0=0, I got > the theoretical signal. > When I compare the experimental and theoretical spectrum I see a mismatch > between the position of the nodes at low wavenumbers. > Having done this, how I have to proceed to correct the experimental data in > order to obtain smalller delta E0 values? > > Thanks in advance, > > Elsa > > --- El *mié, 29/9/10, ifeffit-requ...@millenia.cars.aps.anl.gov < > ifeffit-requ...@millenia.cars.aps.anl.gov>* escribió: > > > De: ifeffit-requ...@millenia.cars.aps.anl.gov < > ifeffit-requ...@millenia.cars.aps.anl.gov> > Asunto: Ifeffit Digest, Vol 91, Issue 28 > Para: ifeffit@millenia.cars.aps.anl.gov > Fecha: miércoles, 29 de septiembre, 2010 14:00 > > Send Ifeffit mailing list submissions to > > ifeffit@millenia.cars.aps.anl.gov<http://es.mc278.mail.yahoo.com/mc/compose?to=ifef...@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-requ...@millenia.cars.aps.anl.gov<http://es.mc278.mail.yahoo.com/mc/compose?to=ifeffit-requ...@millenia.cars.aps.anl.gov> > > You can reach the person managing the list at > > ifeffit-ow...@millenia.cars.aps.anl.gov<http://es.mc278.mail.yahoo.com/mc/compose?to=ifeffit-ow...@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: Aligning Energy scales (Matt Newville) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Tue, 28 Sep 2010 12:55:15 -0500 > From: Matt Newville > <newvi...@cars.uchicago.edu<http://es.mc278.mail.yahoo.com/mc/compose?to=newvi...@cars.uchicago.edu> > > > To: XAFS Analysis using Ifeffit > <ifeffit@millenia.cars.aps.anl.gov<http://es.mc278.mail.yahoo.com/mc/compose?to=ifef...@millenia.cars.aps.anl.gov> > > > Subject: Re: [Ifeffit] Aligning Energy scales > Message-ID: > > <aanlktima_bgt5oo=k-vb-0argwb9ac_w6bcblwgca...@mail.gmail.com<http://es.mc278.mail.yahoo.com/mc/compose?to=k-vb-0argwb9ac_w6bcblwgca...@mail.gmail.com> > > > Content-Type: text/plain; charset=ISO-8859-1 > > Dear Elsa, > > It sounds like you want to adjust the data chi(k) so that deltaE0 is 0 > in a fit. Is that correct, or are you trying to do something else > (say, align the XANES)? If that assumption is correct, you want to > change the E0 used to extract chi(k) from the experimental spectra -- > the E0 of the background subtraction. That is what sets k for the > data. > > If that's not clear or not the right question, let us know, > > --Matt > > On Mon, Sep 27, 2010 at 2:00 PM, Elsa E. Sileo > <si...@qi.fcen.uba.ar<http://es.mc278.mail.yahoo.com/mc/compose?to=si...@qi.fcen.uba.ar>> > wrote: > > I need to align a measured spectra to a theoretically calculated spectra. > > I fitted the first shell obtaining values for deltaE0, sigma^2; delta R > and > > amplitude. > > Then, using the obtained values, and making deltaE0=0, I got the > theoretical > > signal. > > But I do not know how to use this last theoretical fit to align the > spectra. > > Can somebody help me? > > > > Thanks, > > > > Elsa > > > > > > Dra. Elsa E. Sileo > > Solidos Inorganicos > > INQUIMAE - Dto. Qca. Inorganica, Analitica y Qca. Fisica; FCEN, UBA > > Int. G?iraldes 2160, Pabell?n 2, Piso 3, Ciudad Universitaria - C1428EHA > > CABA - Argentina > > Tel: (54 11) 4576 3380 ext. 113 > > Fax: (54 11) 4576 3341 > > e-mail: > > si...@qi.fcen.uba.ar<http://es.mc278.mail.yahoo.com/mc/compose?to=si...@qi.fcen.uba.ar> > > > > > > > > > > _______________________________________________ > > Ifeffit mailing list > > Ifeffit@millenia.cars.aps.anl.gov<http://es.mc278.mail.yahoo.com/mc/compose?to=ifef...@millenia.cars.aps.anl.gov> > > http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit > > > > > > > > ------------------------------ > > _______________________________________________ > Ifeffit mailing list > Ifeffit@millenia.cars.aps.anl.gov<http://es.mc278.mail.yahoo.com/mc/compose?to=ifef...@millenia.cars.aps.anl.gov> > http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit > > > End of Ifeffit Digest, Vol 91, Issue 28 > *************************************** > > ns > > > > _______________________________________________ > Ifeffit mailing list > Ifeffit@millenia.cars.aps.anl.gov > http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit > >
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