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

Re: [Ifeffit] XAFS fitting in xas_viewer and reset of customized
by juejing.liu＠gmail.com 28 Aug '22

28 Aug '22

Hi Matt, Here is the session file for the UO2 fitting. The screenshot blow shows what the customized variables look like right before saving this session. Please feel free to let me know if you need any extra information. Best, Juejing Liu Guo Group Materials Science and Engineering program Alexandra Navrotsky Institute for Experimental Thermodynamics Washington State University Pullman, WA 99164-4630 Office: Fulmer Hall, Room 630 Phone: 208-206-7304

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Re: [Ifeffit] XAFS fitting in xas_viewer and reset of customized variables after save & load cycle
by Liu, Juejing 28 Aug '22

28 Aug '22

Hi Matt, Thanks for the quick response. I just noticed that the data in the screenshot is unpublished data so I may not be able to send you that one. But I will send you a typical UO2 fitting later today (in the larch session) so that you can look. Best, Juejing Liu Guo Group Materials Science and Engineering program Alexandra Navrotsky Institute for Experimental Thermodynamics Washington State University Pullman, WA 99164-4630 Office: Fulmer Hall, Room 630 Phone: 208-206-7304

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Quick Absorption and Scattering (QAS) beamline scientist position at NSLS II
by Stavitski, Eli 26 Aug '22

26 Aug '22

Dear all, We are looking for a beamline scientist for Quick Absorption and Scattering (QAS) beamline (https://www.bnl.gov/nsls2/beamlines/beamline.php?r=7-BM) The full job description is available here https://jobs.bnl.gov/job/upton/beamline-scientist-quick-x-ray-absorption-an… ____________________________________ Eli Stavitski, PhD, Physicist Inner Shell Spectroscopy (ISS) Lead Beamline Scientist National Synchrotron Light Source-II Bldg. 743, Brookhaven National Laboratory Upton, NY 11973-5000 631 344 8641 istavitski(a)bnl.gov<mailto:istavitski@bnl.gov> https://www.bnl.gov/ps/beamlines/beamline.php?r=8-ID

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third cumulant in Larch
by Andy Zhang 19 Aug '22

19 Aug '22

Dear all, I have a quick question related to EXAFS fitting using Larch. I wonder how to include the third cumulant in the fitting. I tried to add "third" in the "pars" section, but it seems it did not work. [image: image.png] Thanks a lot for your help! Have a nice day! Best, Harry

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Environmental geochemist position at DOE-National Energy Technology Laboratory
by Mengling Stuckman 18 Aug '22

18 Aug '22

Dear ifeffit members, Recently we are interested in hiring an environmental geochemist for our critical mineral sustainability program at NETL, Pittsburgh, PA. Synchrotron experience is a plus. U.S. citizens are strongly preferred. Here is the specific job posting. https://leidos.wd5.myworkdayjobs.com/External/job/Pittsburgh-PA/Environment… Feel free to pass along this information to your students who are interested. If you have any questions related to the post, feel free to contact me at mengling.stuckman(a)netl.doe.gov Thanks and have a nice day, Mengling -- Mengling Stuckman Leidos Technical Fellow National Energy Technology Laboratory U.S. Department of Energy Pittsburgh, PA mengling.stuckman(a)netl.doe.gov Office: 412-386-7387

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Using larch for feff Fitting -> simple 4 parameter fit
by Mangold, Stefan (IPS) 18 Aug '22

18 Aug '22

Dear all, I try to use larch for Feff Fitting. For a first start, I liked the option of Artemis with the „simple 4 parameter fit“. Larch produces for every path an independent dear and sigma2. Is there a simple way to make this simple 4 parameter fit also in larch? best regards Stefan Mangold

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XAFS short course at BNL: November 2-4
by Anatoly Frenkel 09 Aug '22

09 Aug '22

Dear subscribers: Please spread the word to those who may be interested in our next annual short course at BNL on X-ray absorption fine structure. The dates are: November 2-4. It will be virtual. The level will be intermediate to advance (last year it was a beginner level). As in the past, lectures, discussions and software demonstration sessions will be on Wednesday and Thursday, and the full day data analysis practicum will be on Friday. More information about the course and the link to the application form will appear soon on BNL web site, and on the web site of the Synchrotron Catalysis Consortium (SCC). Regards, Anatoly ------------------------------------------------------------------- Anatoly I. Frenkel Professor Department of Materials Science and Chemical Engineering Stony Brook University Stony Brook, NY 11794 Email: anatoly.frenkel(a)stonybrook.edu <https://mail.bnl.gov/OWA/redir.aspx?C=F6wCGt4adziN6IvpdRQ-rWdgy3Oaoif_x-0yb…> http://you.stonybrook.edu/frenkel Co-Director and Spokesperson, Synchrotron Catalysis Consortium (SCC) at BNL http://you.stonybrook.edu/scc2 Joint Appointment: Senior Chemist Chemistry Division, Brookhaven National Laboratory Upton, NY 11973. Ph: 631-344-3013. Group: 631-344-3494 Email: frenkel(a)bnl.gov https://www.bnl.gov/staff/frenkel -------------------------------------------------------------------

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Standardized Spectra
by Kyle Draim 08 Aug '22

08 Aug '22

Hello! I don't have any X-Ray data to analyze in your app, I'm just seeking a visual display of each element's standardized/accepted X-Ray spectra (instead of a table of numbers). So far, I've downloaded the application, but I'm stuck on how to find this information. I would greatly appreciate it if you would be willing to provide the necessary steps to accessing this information or if you would be willing to direct me to the right source for that info. Thanks, Kyle

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xraylarch
by Paul Fons 06 Aug '22

06 Aug '22

Hi. Due to the difficulties of getting demeter to work on the Apple M1 machines, I have started to use xraylarch and so far I like the interface as well as the possibility of scripting later on. I had a couple of observations and a question regarding xraylarch usage that I hope could be addressed here. First, one can load multiple spectra into the (feff) fitting window. It seems, however, that which paths are selected are universal (the selected paths are used for all exafs spectra). Does this mean that multiple edge fitting is not possible. If multiple edge fitting is possible, how is it done? In the fitting window, one can have several spectra loaded and one can select all or some of the spectra to be fit. The interface seems like it was designed for multiple edge fitting, but is it? Second, it is strange that whenever a parameter is changed that the fitting variable settings (fixed, vary, constrain) are reset. For complex fits, this generates a lot of unnecessary clicking (and the corresponding mistake possibilities) Third, when one reads in several different feff calculations, one would, in principle, like to have a different value of e0 (the origin of energy offset) for each feff calculation. By default when a feff calculation is read in the variable e0 is defined. When one defines alternative energy offset variables for the different feff calculations and deletes the original e0 value, something strange happens. Accessing the “Edit Parameters” window results in e0 reappearing (even though it has been manually deleted previously). Is this a feature? The same thing may happen for other “automatic” variables as well. Four. This is really a feature request. When a variable is unused (lets say some additional paths are introduced in the fitting process and a new fit without them is attempted), the choices in the parameter list are (fix, vary, and constrain). There is no option to “skip” like in Artemis. Obviously, one can choose fix, but in doing so the unused variable shows up in the fit result summary and is somewhat confusing. It would be subjectively better to have the option to “skip” a variable and not have it show up in the fit summary. Just some initial thoughts...

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VC and V(CO)6 data to share
by Ismael Graff 06 Aug '22

06 Aug '22

Dear XAFS enthusiasts, would anyone have XAFS data of crystalline vanadium carbide (VC) and vanadium hexacarbonyl (V(CO)6) to share? In the case of V(CO)6 I´m having great trouble of finding any published measurement! I found papers for Cr(CO)6, but not V(CO)6. Bibliographical references are also welcome. All the best, Ismael. -- ************************************ * Ismael Graff * * * * Universidade Federal do Paraná * * Departamento de Física, CP 19044 * * 81531-980, Curitiba, Brazil. * * Tel (office): +55 41 3361 3093 * * Tel (Lab): +55 41 3361 3427 * * Fax: +55 41 3361 3418 * * http://fisica.ufpr.br/graff * * * * "DOCENDO DISCIMUS" * ************************************

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