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Problem with handling doped material
by Rana, Jatinkumar Kantilal 20 Oct '11

20 Oct '11

Dear Ifeffit users, I apologize for my previous post with subject "Difficulty in running feff8.2" being ill-defined and lacking adequate supporting informations, I try to redefine the problem again. I want to perform EXAFS fit on data for Li2Mn1.5Ni0.5O4 material measured on Mn K-edge. (i.e. case of handling dopant by modifying feff.inp files) I used Li2Mn2O4 structure (attached as Li2Mn2O4.inp file) to generate feff.inp file With Mn core atom (attached as Li2Mn2O4_feff.inp) and run through Feff8.2. It worked well. Now, when I modified Li2Mn2O4_feff.inp file such that Mn is core atom but all back scatterers are now Ni instead of Mn (attached as Li2Ni2O4_feff.inp), feff8.2 terminates after 17 SCF iterations. I have no idea why, since it never happened before. Looking at both feff.inp files they are identical except with the fact that in case of Li2Ni2O4_feff.inp, I replaced all Mn back scatterers with Ni. Am I doing something wrong (unknowingly) ?? I am using Windows 7 machine but I tried it on another windows xp machine also and the result is same. Can anyone on mailing list help me getting out of these problem ?? Any help would be much appreciated. With best regards, Jatin -----Original Message----- From: ifeffit-bounces(a)millenia.cars.aps.anl.gov [mailto:ifeffit-bounces@millenia.cars.aps.anl.gov] On Behalf Of ifeffit-request(a)millenia.cars.aps.anl.gov Sent: Dienstag, 18. Oktober 2011 19:00 To: ifeffit(a)millenia.cars.aps.anl.gov Subject: Ifeffit Digest, Vol 104, Issue 24 Send Ifeffit mailing list submissions to ifeffit(a)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(a)millenia.cars.aps.anl.gov You can reach the person managing the list at ifeffit-owner(a)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. Difficulty in running feff8.2 (Rana, Jatinkumar Kantilal) ---------------------------------------------------------------------- Message: 1 Date: Tue, 18 Oct 2011 15:10:31 +0000 From: "Rana, Jatinkumar Kantilal" <jatinkumar.rana(a)helmholtz-berlin.de> To: "ifeffit(a)millenia.cars.aps.anl.gov" <ifeffit(a)millenia.cars.aps.anl.gov> Subject: [Ifeffit] Difficulty in running feff8.2 Message-ID: <6CA1A94BC28ABA4F9E1D360B3E249AEC0E3BC4A8@didag1> Content-Type: text/plain; charset="us-ascii" Dear ifeffit users, Recently, I am facing difficulty in running feff8.2 on one particular feff.inp file. I have measured Mn K-edge data for Li2Mn1.5Ni0.5O4. I want to perform feff calculation of Li2Mn1.5Ni0.5O4 in order to fit the data. I have structural data for Li2Mn2O4. To have an overall feff calculation of Li2Mn1.5Ni0.5O4, I need to perform feff calculation two times, i.e., one with Li2Mn2O4 (with Mn as core) and second with Li2Ni2O4 (i.e. with Mn as core and rest of Mn atoms replaced by Ni). Then I can add both feff calculations appropriately to generate resultant theoretical chi(k) and go ahead with fitting. The problem is, I could successfully run feff8.2 on Li2Mn2O4, but when I run it on Li2Ni2O4 it stops after performing few iterations without any notifications. I am not able to understand why feff terminates half way. I have never faced such problem before. Can anyone help me ? Please see the attached feff.inp file which I am trying to run. I have activated SCF card in that. Many thanks in advance !! With Best regards, Jatin ________________________________ Helmholtz-Zentrum Berlin f?r Materialien und Energie GmbH Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren e.V. Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. Vorsitzende Dr. Beatrix Vierkorn-Rudolph Gesch?ftsf?hrer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer Sitz Berlin, AG Charlottenburg, 89 HRB 5583 Postadresse: Hahn-Meitner-Platz 1 D-14109 Berlin http://www.helmholtz-berlin.de -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://millenia.cars.aps.anl.gov/pipermail/ifeffit/attachments/20111018/4a5…> -------------- next part -------------- A non-text attachment was scrubbed... Name: feff.inp Type: application/octet-stream Size: 9986 bytes Desc: feff.inp URL: <http://millenia.cars.aps.anl.gov/pipermail/ifeffit/attachments/20111018/4a5…> ------------------------------ _______________________________________________ Ifeffit mailing list Ifeffit(a)millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit End of Ifeffit Digest, Vol 104, Issue 24 **************************************** ________________________________ Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren e.V. Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. Vorsitzende Dr. Beatrix Vierkorn-Rudolph Geschäftsführer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer Sitz Berlin, AG Charlottenburg, 89 HRB 5583 Postadresse: Hahn-Meitner-Platz 1 D-14109 Berlin http://www.helmholtz-berlin.de

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Calvin ZnO
by mattie.peck＠huskers.unl.edu 19 Oct '11

19 Oct '11

Hello Ifeffit Subscribers: I was wondering if somebody could send me the files that Scott Calvin posted about a worked example of ZnO. The Ifeffit site won't let me download the zipped file. Thanks, Mattie Peck

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Difficulty in running feff8.2
by Rana, Jatinkumar Kantilal 18 Oct '11

18 Oct '11

Dear ifeffit users, Recently, I am facing difficulty in running feff8.2 on one particular feff.inp file. I have measured Mn K-edge data for Li2Mn1.5Ni0.5O4. I want to perform feff calculation of Li2Mn1.5Ni0.5O4 in order to fit the data. I have structural data for Li2Mn2O4. To have an overall feff calculation of Li2Mn1.5Ni0.5O4, I need to perform feff calculation two times, i.e., one with Li2Mn2O4 (with Mn as core) and second with Li2Ni2O4 (i.e. with Mn as core and rest of Mn atoms replaced by Ni). Then I can add both feff calculations appropriately to generate resultant theoretical chi(k) and go ahead with fitting. The problem is, I could successfully run feff8.2 on Li2Mn2O4, but when I run it on Li2Ni2O4 it stops after performing few iterations without any notifications. I am not able to understand why feff terminates half way. I have never faced such problem before. Can anyone help me ? Please see the attached feff.inp file which I am trying to run. I have activated SCF card in that. Many thanks in advance !! With Best regards, Jatin ________________________________ Helmholtz-Zentrum Berlin f?r Materialien und Energie GmbH Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren e.V. Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. Vorsitzende Dr. Beatrix Vierkorn-Rudolph Gesch?ftsf?hrer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer Sitz Berlin, AG Charlottenburg, 89 HRB 5583 Postadresse: Hahn-Meitner-Platz 1 D-14109 Berlin http://www.helmholtz-berlin.de

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Re: [Ifeffit] Ifeffit Digest, Vol 104, Issue 22
by David Sprouster 14 Oct '11

14 Oct '11

Julian: I agree with Anatoly. The amplitude of the EXAFS is quite large. I have seen a similar effect in metal foils and NP samples when you forget to take the log of the I0 and IT. This also forces the S02 factor to be artificially high (like it is for your samples) when fitting in Artemis. Maybe try to re-adjust the raw data file upon importing into Athena and then see if your spectra (intensities, features and S02) line up better with those from the literature (and from the very useful Lytle database on XAFS.org) Hope that helps Dave On Fri, Oct 14, 2011 at 9:14 AM, <ifeffit-request(a)millenia.cars.aps.anl.gov>wrote: > Send Ifeffit mailing list submissions to > ifeffit(a)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(a)millenia.cars.aps.anl.gov > > You can reach the person managing the list at > ifeffit-owner(a)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: Gold Nanoparticle first shell fitting (Kaiser, Julian) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Fri, 14 Oct 2011 14:14:00 +0000 > From: "Kaiser, Julian" <julian.kaiser(a)helmholtz-berlin.de> > To: XAFS Analysis using Ifeffit <ifeffit(a)millenia.cars.aps.anl.gov> > Subject: Re: [Ifeffit] Gold Nanoparticle first shell fitting > Message-ID: <DE491AE4BEF1864DB8831D1BC0E7EA1A0E554D33@didag2> > Content-Type: text/plain; charset="iso-8859-1" > > Dear Anatoly, > > thanks a lot for your reply! > I don't see the problem yet. In the attached file > ("different_Au_foils.prj), there are two different gold reference foils > measured at two different synchrotrons. There is some difference but not > realy much. Could you please describe the regions that are worse comparing > my gold foil-file to yours, or if possible, attache the file with both foils > or at least a screenshot of the plot? > > Best regards, > Julian > > > > ________________________________ > Von: ifeffit-bounces(a)millenia.cars.aps.anl.gov [ > ifeffit-bounces(a)millenia.cars.aps.anl.gov]" im Auftrag von "Anatoly I > Frenkel [afrenke2(a)yu.edu] > Gesendet: Dienstag, 11. Oktober 2011 20:29 > Bis: XAFS Analysis using Ifeffit > Betreff: Re: [Ifeffit] Gold Nanoparticle first shell fitting > > > Something is horribly wrong with the data here. > > I overplotted your reference Au foil against mine, and yours has distorted > XANES and too high EXAFS intensity compared to my data. Your amplitude > factor is 1.54 which also confirms that something was wrong in the > experiment. Perhaps - a misalignment? The NP data also look strange... > > I would not focus on the NP analysis until you figure out why your foil > data is so strange. > > > > > > ________________________________ > From: ifeffit-bounces(a)millenia.cars.aps.anl.gov [ > ifeffit-bounces(a)millenia.cars.aps.anl.gov] on behalf of Kaiser, Julian [ > julian.kaiser(a)helmholtz-berlin.de] > Sent: Tuesday, October 11, 2011 1:06 PM > To: ifeffit(a)millenia.cars.aps.anl.gov > Subject: [Ifeffit] Gold Nanoparticle first shell fitting > > Dear Ifeffit Community, > > I'm trying to fit a gold nanoparticle in the size of about 2 nm that is > immobilized by polymers. For my research it's enought to fit the first shell > only, becaues all I would like to analyze is the atomic distance in the > nanoparticle. After the (hopefully) correct background substraction in > Athena (athena file attached), there is a shoulder at approx. 2.1 Angstr?m > in the R-space. > In Artemis, fitting this shoulder seems not to be possible, while the fit > for the reference (gold foil) seems to be fine. (both artemis files are > attached to the e-mail). > If the k-range is decreased from 12.388 to a value between 9 an 10, the > shoulder disappears and the fit works fine. But I think by this change I > might modify the data too much. > Would be really nice, if sombody has an idea how to deal with the problem, > to get a hint how to solve this. > > Thanks a lot, > Julian > > ________________________________ > > Helmholtz-Zentrum Berlin f?r Materialien und Energie GmbH > > Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren > e.V. > > Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. > Vorsitzende Dr. Beatrix Vierkorn-Rudolph > Gesch?ftsf?hrer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer > > Sitz Berlin, AG Charlottenburg, 89 HRB 5583 > > Postadresse: > Hahn-Meitner-Platz 1 > D-14109 Berlin > > http://www.helmholtz-berlin.de > > ________________________________ > > Helmholtz-Zentrum Berlin f?r Materialien und Energie GmbH > > Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren > e.V. > > Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. > Vorsitzende Dr. Beatrix Vierkorn-Rudolph > Gesch?ftsf?hrer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer > > Sitz Berlin, AG Charlottenburg, 89 HRB 5583 > > Postadresse: > Hahn-Meitner-Platz 1 > D-14109 Berlin > > http://www.helmholtz-berlin.de >

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Re: [Ifeffit] Ifeffit Digest, Vol 104, Issue 22
by Lauren Glowzenski 14 Oct '11

14 Oct '11

UNSUBSCRIBE PLEASE On Fri, Oct 14, 2011 at 10:14 AM, <ifeffit-request(a)millenia.cars.aps.anl.gov > wrote: > Send Ifeffit mailing list submissions to > ifeffit(a)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(a)millenia.cars.aps.anl.gov > > You can reach the person managing the list at > ifeffit-owner(a)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: Gold Nanoparticle first shell fitting (Kaiser, Julian) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Fri, 14 Oct 2011 14:14:00 +0000 > From: "Kaiser, Julian" <julian.kaiser(a)helmholtz-berlin.de> > To: XAFS Analysis using Ifeffit <ifeffit(a)millenia.cars.aps.anl.gov> > Subject: Re: [Ifeffit] Gold Nanoparticle first shell fitting > Message-ID: <DE491AE4BEF1864DB8831D1BC0E7EA1A0E554D33@didag2> > Content-Type: text/plain; charset="iso-8859-1" > > Dear Anatoly, > > thanks a lot for your reply! > I don't see the problem yet. In the attached file > ("different_Au_foils.prj), there are two different gold reference foils > measured at two different synchrotrons. There is some difference but not > realy much. Could you please describe the regions that are worse comparing > my gold foil-file to yours, or if possible, attache the file with both foils > or at least a screenshot of the plot? > > Best regards, > Julian > > > > ________________________________ > Von: ifeffit-bounces(a)millenia.cars.aps.anl.gov [ > ifeffit-bounces(a)millenia.cars.aps.anl.gov]" im Auftrag von "Anatoly I > Frenkel [afrenke2(a)yu.edu] > Gesendet: Dienstag, 11. Oktober 2011 20:29 > Bis: XAFS Analysis using Ifeffit > Betreff: Re: [Ifeffit] Gold Nanoparticle first shell fitting > > > Something is horribly wrong with the data here. > > I overplotted your reference Au foil against mine, and yours has distorted > XANES and too high EXAFS intensity compared to my data. Your amplitude > factor is 1.54 which also confirms that something was wrong in the > experiment. Perhaps - a misalignment? The NP data also look strange... > > I would not focus on the NP analysis until you figure out why your foil > data is so strange. > > > > > > ________________________________ > From: ifeffit-bounces(a)millenia.cars.aps.anl.gov [ > ifeffit-bounces(a)millenia.cars.aps.anl.gov] on behalf of Kaiser, Julian [ > julian.kaiser(a)helmholtz-berlin.de] > Sent: Tuesday, October 11, 2011 1:06 PM > To: ifeffit(a)millenia.cars.aps.anl.gov > Subject: [Ifeffit] Gold Nanoparticle first shell fitting > > Dear Ifeffit Community, > > I'm trying to fit a gold nanoparticle in the size of about 2 nm that is > immobilized by polymers. For my research it's enought to fit the first shell > only, becaues all I would like to analyze is the atomic distance in the > nanoparticle. After the (hopefully) correct background substraction in > Athena (athena file attached), there is a shoulder at approx. 2.1 Angstr?m > in the R-space. > In Artemis, fitting this shoulder seems not to be possible, while the fit > for the reference (gold foil) seems to be fine. (both artemis files are > attached to the e-mail). > If the k-range is decreased from 12.388 to a value between 9 an 10, the > shoulder disappears and the fit works fine. But I think by this change I > might modify the data too much. > Would be really nice, if sombody has an idea how to deal with the problem, > to get a hint how to solve this. > > Thanks a lot, > Julian > > ________________________________ > > Helmholtz-Zentrum Berlin f?r Materialien und Energie GmbH > > Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren > e.V. > > Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. > Vorsitzende Dr. Beatrix Vierkorn-Rudolph > Gesch?ftsf?hrer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer > > Sitz Berlin, AG Charlottenburg, 89 HRB 5583 > > Postadresse: > Hahn-Meitner-Platz 1 > D-14109 Berlin > > http://www.helmholtz-berlin.de > > ________________________________ > > Helmholtz-Zentrum Berlin f?r Materialien und Energie GmbH > > Mitglied der Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren > e.V. > > Aufsichtsrat: Vorsitzender Prof. Dr. Dr. h.c. mult. Joachim Treusch, stv. > Vorsitzende Dr. Beatrix Vierkorn-Rudolph > Gesch?ftsf?hrer: Prof. Dr. Anke Rita Kaysser-Pyzalla, Dr. Ulrich Breuer > > Sitz Berlin, AG Charlottenburg, 89 HRB 5583 > > Postadresse: > Hahn-Meitner-Platz 1 > D-14109 Berlin > > http://www.helmholtz-berlin.de >

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beamline for Al EXAFS
by Kompch, Alexander 13 Oct '11

13 Oct '11

Dear all, for the analysis of the location of the Al-dopant in ZnO, I am looking for suitable EXAFS beamlines. Dopant concentrations are 1-10%. So far I have only found ALS 6.3.1 and NSLS X15B. Can anybody recommend beamlines for Al EXAFS? My EXAFS experience is so far limited to the high energy range with signal detection in transmission (ionization chambers) and fluorescence (multi-element Ge-detectors). At such low energies as 1.5 keV for Al-K, the sample needs to be in vacuum, transmission will not work and Ge detectors probably the same. Does anybody have experience with Al-EXAFS, and can share a little about setup and what other complications to expect? Thank you, Alex.

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Re: [Ifeffit] XANES fitting
by Matt Newville 12 Oct '11

12 Oct '11

Hi Riti, I hope it's OK that I'm sending this to the ifeffit mailing list, as there might be other interesting perspectives on your questions. On Tue, Oct 11, 2011 at 3:47 PM, Ritimukta Sarangi <ritis(a)stanford.edu> wrote: > Hi Matt, > This is Riti again. This time I have a question about EXAFS, which you are an expert on :-) I would like to get your view on > systematic errors in EXAFS. Say the data were collected on a standard EXAFS beamline like 7-3 at SSRL. The data have > been collected using fluorescence mode and a 30 element Ge detector. The data are modest, between k=2-15 A. > > I used to quote in my papers that typical statistical and systematic errors lead to a total error in first shell distances of > +-0.02 A. I know it can be more than that in some circumstances but then I tried to look at it a little more closely to > separate out the systematic error from all sources (instrument, measurement, detector, Analysis), but I could not find a > good reference. I understand that this is a difficult number to estimate. I was hoping that you could shed some light on it. > Thanks! > -Riti > I'm not sure of a good general reference for that either, though perhaps some of the papers from Corwin Booth are a good place to start? Quoting +/- 0.02 Ang seems like a reasonable estimate for a typical value, but that's hardly rigorous. My sense is that it's pretty challenging to separate "systematic" and "random" noise for most data sets. Fluorescence data from a solid-state detector is probably the best-case for such a separation, because you have multiple detector elements or repeated scans, and usually the individual detectors or scans really are dominated by statistical fluctuations. If you add detector elements or scans together until the noise in the data (or variations in estimated parameters or estimated error bars) stops getting better, systematic errors are starting to be noticeable. Eventually, as you increase the fluorescence counts, the fits will stop improving, which should be when systematic errors dominate. --Matt

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building feff input file; position of absorbing atom(s)
by Dreher Marian 12 Oct '11

12 Oct '11

Dear Feff community, I have a question concerning the position of the absorbing atom when creating a feff input file. I am trying to calculate the EXAFS for a disk-like Ru nanoparticle that I "built" from literature data using the program Diamond. The particle has 3 atomic layers, looks somewhat half-pyramidal and consists of about 80 atoms. I then exported the atom positions and used them as an input for feff. Since my cluster is far from being a bulk structure, the spectrum I get strongly depends on where I place my absorbing atom. In this cluster the atoms can be grouped by common coordination number. Do I have to manually calculate the EXAFS for every single group and then calculate the mean spectrum weighted with the degeneracy of each group or is there a smarter way to do that? Many thanks, Marian. Marian Dreher, Dipl. Chem. PhD Student, Catalytic Process Engineering Group Paul Scherrer Institut General Energy Research (ENE) Laboratory for Bioenergy and Catalysis Office: OVGA/115 CH-5232 Villigen PSI Switzerland Phone: +41 (0)56 310 2937 email: marian.dreher(a)psi.ch

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Re: [Ifeffit] lifetime broadening of pre-edge peaks
by vikrai＠comcast.net 11 Oct '11

11 Oct '11

Hi Matthew, The lifetime broadening of the XANES features is determined by the time of life of the final excited state. This two-particle excitation includes the core hole and the photoelectron. The core hole may decay due to the various radiation or non radiation processes. The photoelectron state may decay due to inelastic collisions, plasmon excitations, etc. The time of life of the core hole, I believe, does not depend on the photon energy whilst the last is near the absorption edge. But it is not true for the photoelectron. It is better to write “photoelectron” because some of the pre-edge peaks which exist in the transition metal oxides spectra are in fact X-ray excitons and no photoemission can be observed. In these cases the final states are bound states and it is purely many electron effect caused by the core-hole - “photoelectron” interaction. For those pre-edge peaks the life time broadening is determined entirely by the core-hole life time. But as soon as photoelectron jumps to the conduction band the mechanisms of its inelastic scattering turn on and one should take into account the time of life of photoelectron (now without quotes). Unfortunately, it is difficult to determine which pre-edge peaks are excitonic and which are not. As it was already mentioned there are other mechanisms of broadening of the pre-edge peaks. For diamagnetic atoms it is thermal vibrations, for paramagnetic ones it is multiplet interactions as well. Good luck. Victor Krayzman.

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particle size and coordination number in Ru nanoparticles on carbon
by Dreher Marian 11 Oct '11

11 Oct '11

Dear Ifeffit Community, I am currently trying to extract the particle size of Ru supported on carbon from EXAFS data. I also recorded spectra of a Ru foil as a bulk reference sample. So, my approach is to fit the first coordination shell of my bulk reference, setting CN to 12. From that I get a value for s02. I'm then using this value in the first shell fit for the Ru nanoparticles in order to get the coordination number. However, the fit suggests that CN is still pretty much 12. What is changing drastically, though, is sigma^2 which usually doubles in value compared to the bulk sample. That makes sense, I guess, since there might be higher disorder in the nanoparticles. Obviously, there is a chance that my nanoparticles are rather big, in which case CN would be close to 12. However, STEM and HRTEM pictures suggest that the Ru particles are between 1 and 2 nm in diameter. I'm just starting to get into EXAFS analysis and pretty clueless right now about how to approach this. Happy about any input, many thanks, Marian.

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