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

Dynamic XAFS Simulations?
by Hunter Allison 23 Jan '19

23 Jan '19

Hi, I'm a graduate student at the University of California, Irvine. Firstly, thank you for all the copious resources. It is a treasure trove of information and a beacon of light for someone just starting out. Let's begin with some brief background. In my research group, we intend to perform pump-probe spectroscopy with attosecond x-ray probes. The Professor says that we can use XAFS to study how the electrons move on these very short timescales. While the system is being setup and other experiments are being conducted, my Professor wants me to figure out how to do simulations of XAFS. This is a bit of a daunting order, since I've never simulated anything before and only have basic programming knowledge. The only direction I have is, "Try Google.". So, today, I've been "trying Google" and found my way to here. Since, I don't really know what I'm doing, I thought I try asking and finding out if anyone else does this sort of thing: How/where does one do simulations of dynamic XAFS? Where would I get started? (Please forgive me if this question has been answered somewhere else or if it seems profoundly dumb or too broad. I'm really just looking for some more direction. Perhaps, it could be that nobody does this and, in that case, I need to figure out how to model this myself. Wow! That thought seems daunting.) For example, let's say I want to find out how the x-ray adsorption of a carbon foil like Graphene would change on attosecond time scales as it's heated by a femtosecond laser and electrons move. Is there a program or code out there that people use to model this sort of thing?

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XAS data for Nickel Chloride
by Gill, Simerjeet 18 Jan '19

18 Jan '19

Hi, I am working with a molten salt system with Nickel Chloride as one of the components. If you have measured XAS data on anhydrous and hydrated Nickel Chloride at RT and elevated temperature, I would appreciate you sharing your data. Thanks in advance for your help! Simer Simerjeet K Gill, Materials Scientist, Nuclear Science and Technology Department, Brookhaven National Lab, Upton, NY 11973

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求助Athena软件32位电脑安装包，谢谢
by 2225295803 16 Jan '19

16 Jan '19

你好，我是天津大学马新宾课题组的硕士研究生袭雨杉，我的电脑是32位的，请问有32位的EXAFS分析软件Athena吗？可以发给我吗？谢谢

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Advice on using Athena for XANES LCF on spectra with a small edge step?
by Mike Massey 16 Jan '19

16 Jan '19

Hi All, Does anyone have advice for LCF of spectra with a small edge step? I've recently found myself with more and more issues fitting spectra like the one shown in the attached photo, where the spectrum is of good quality, but the fits end up not working out due to normalization (as far as I can tell). Sadly, I have so far ended up just throwing these fits out, but I'm hoping there is a better solution out there that someone might be able to recommend. One solution is "get more of the element of interest," as a beamline scientist recently told me. I'm just reluctant to really load it up in the data collection, because at 2 keV I get nervous about artifacts like self-absorption. Is there a better way? What am I missing? Thanks for your thoughts, Mike

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Nickel Chloride XAS data at RT and 320C
by Gill, Simerjeet 15 Jan '19

15 Jan '19

Hi, I am working with a molten salt system with Nickel Chloride as one of the components. If you have measured XAS data on anhydrous and hydrated Nickel Chloride at RT and 320C, I would really appreciate if you could share the raw data with me. Thanks in advance for your help! Simer Simerjeet K Gill, Materials Scientist, Nuclear Science and Technology Department, Brookhaven National Lab, Upton, NY 11973 -----Original Message----- From: Ifeffit <ifeffit-bounces(a)millenia.cars.aps.anl.gov> On Behalf Of ifeffit-request(a)millenia.cars.aps.anl.gov Sent: Friday, January 11, 2019 12:20 PM To: ifeffit(a)millenia.cars.aps.anl.gov Subject: Ifeffit Digest, Vol 191, Issue 7 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: Standard deviation of R value (Matt Newville) 2. Re: Standard deviation of R value (Anatoly Frenkel) 3. Re: Standard deviation of R value (Erin Finley) ---------------------------------------------------------------------- Message: 1 Date: Fri, 11 Jan 2019 10:04:49 -0600 From: Matt Newville <newville(a)cars.uchicago.edu> To: XAFS Analysis using Ifeffit <ifeffit(a)millenia.cars.aps.anl.gov> Subject: Re: [Ifeffit] Standard deviation of R value Message-ID: <CA+7ESbo=kOiHZx9skxwv6qzHADH9q5Rh2u=Y8np+5AB-XqRyiA(a)mail.gmail.com> Content-Type: text/plain; charset="utf-8" Hi Erin, On Fri, Jan 11, 2019 at 8:19 AM Erin Finley <efinley9033(a)gmail.com> wrote: > Hello, I see in many publications the R value reported with a standard > deviation. However, when I look at my resulting data from a fit I > don't see one listed. I am still new to EXAFS research and so I am > wondering where I can get this information. I am assuming I need to > calculate it from another parameter I am just not sure which one. > > The uncertainties in R are typically in the fit report. But also, we typically refine a "delR" parameter that is R - Reff, where Reff is the distance (half path-lengh) for the scattering path. So, if you don't see an uncertainty reported for R but do see an uncertainty for delR (or whatever parameter name you used), use that. The uncertainty in R will (normally) be the uncertainty in delR. If I'm misunderstanding the question, pleas give more details about what you are doing. --Matt Thanks for your help! > Cheers, > > -- > Erin Finley > PhD Candidate > Brgoch Research Group > Department of Chemistry > University of Houston > _______________________________________________ > Ifeffit mailing list > Ifeffit(a)millenia.cars.aps.anl.gov > http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit > Unsubscribe: http://millenia.cars.aps.anl.gov/mailman/options/ifeffit > -- --Matt Newville <newville at cars.uchicago.edu> 630-252-0431

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Standard deviation of R value
by Erin Finley 11 Jan '19

11 Jan '19

Hello, I see in many publications the R value reported with a standard deviation. However, when I look at my resulting data from a fit I don't see one listed. I am still new to EXAFS research and so I am wondering where I can get this information. I am assuming I need to calculate it from another parameter I am just not sure which one. Thanks for your help! Cheers, -- Erin Finley PhD Candidate Brgoch Research Group Department of Chemistry University of Houston

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Postdoc at CHESS
by Kenneth David Finkelstein 11 Jan '19

11 Jan '19

Would you please post the attached announcement of a Postdoc position at CHESS? Cornell High Energy Synchrotron Source (CHESS) at Cornell University is completing a major upgrade of its facilities and is seeking a Postdoctoral Associate interested in using x-ray spectroscopy to study biology, chemistry, materials science, and catalysis. Thank you, Ken Finkelstein

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Unwanted rescaling of energy axis when importing ascii file into Athena (Demeter 0.9.26)
by Lukas Grote 09 Jan '19

09 Jan '19

Hello, I am reporting an apparent bug in Athena (Demeter 0.9.26, Windows 10). When I import high energy resolution XAS data from an ascii file, the energy axis is automatically rescaled to 1.2eV step size, thus drastically reducing the resolution of the data. When the imported data has energy steps larger than 1.2eV, no rescaling occurs. This issue may be similar to the one reported in March 2018 under the topic "Athena (Demeter 0.9.26) does not import all datapoints from ascci file". However, the issue I am seeing always results in 1.2eV steps in the imported data. If my original file hast 0.3eV steps, the number of points is reduced by a factor of 4. If it has 0.6eV steps, the number of points is reduced by a factor of 2. I couldn't find any option to switch this recaling on / off, or to change the target energy step size. The problem does not occur with Demeter 0.9.25. Attached please find two screenshots of the data import dialog for both versions of Demeter. The plots show the difference in energy scale. I also attached the original data file "no_rebin.dat" as well as spectra exported from both Demeter versions, one of them showing the 1.2eV steps. Thank you and all the best, Lukas -- Lukas Grote University of Hamburg Center for Hybrid Nanostructures Institute for Nanostructures and Solid State Physics Luruper Chaussee 149, Bld. 600, Room 2.62 22761 Hamburg Germany +49 40 42838 1614

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Fwd: FW: Postdoctoral Research Associate positions
by Anatoly Frenkel 08 Jan '19

08 Jan '19

Dear IFEFFIT mailing list subscribers: Sharing this on behalf of colleagues. The MSEE EFRC at Brookhaven National Laboratory has two postdoctoral positions available immediately. Please find the advertisements with contact information in the attachments. Please forward this info to anyone you believe may be interested in this opportunity. While the both positions expect expertise in multiple methods, I was requested to pass it along to this list specifically because of the PI's interest to develop strong XAFS component for the purpose of this project. Regards, Anatoly ------------------------------------------------------------------- Anatoly I. Frenkel Stony Brook University *From:* Lee, Patricia A *On Behalf Of *Ecker, Lynne *Sent:* Tuesday, January 08, 2019 11:32 AM *Subject:* Postdoctoral Research Associate positions Dear Colleagues, We are seeking candidates for postdoctoral Research Associate positions within the Energy Frontier Research Center (EFRC) on Molten Salts in Extreme Environments at Brookhaven National Laboratory. Information about the positions is summarized below and two flyers are attached to this message. We would appreciate you sharing these opportunities with students, postdocs and other contacts. Please contact us if you have questions. Best regards, Lynne E. Ecker, Chair Nuclear Science and Technology Department Brookhaven National Laboratory Tel: (631) 344-2538 Email: lecker(a)bnl.gov James Wishart, Director, Molten Salts in Extreme Environments EFRC Brookhaven National Laboratory Tel: (631) 344-4327 Email: wishart(a)bnl.gov ***** The Energy Frontier Research Center on Molten Salts in Extreme Environments (EFRC/MSEE) at Brookhaven National Laboratory (BNL) is pleased to announce that we are hiring Postdoctoral Research Associates. These positions will be part of a collaborative, multi-institution team performing electrochemical, structural (x-ray and neutron), spectroscopic (optical and x-ray), kinetics, and computational studies of molten salt and solute structure, speciation and reactivity in the bulk and at interfaces. The MSEE Center’s scientific mission is to provide fundamental, atomic-level understanding of bulk and interfacial molten salts, and the effects of molten salt exposure on interfaces, in support of their use in molten salt nuclear reactors. To this end, we are developing novel in-situ synchrotron, electrochemical and electron microscopy techniques for investigating high-temperature molten salts. Two positions require a Ph.D. degree in chemistry, physics, materials science or a related field. The interdisciplinary research will focus on structural, spectroscopic, and electrochemical investigations of molten salts, solutes in them, and liquid-solid interfaces. A third position requires a Ph.D. degree in chemistry or a related field and primarily involves pulse radiolysis investigations of reaction kinetics in molten salts, in pure form and in mixtures containing other salts and metal ions. To find detailed descriptions of the position requirements and apply online, go to https://jobs.bnl.gov and search for “molten salts.” For Job ID 1411, hands-on experience in either X-ray diffraction, reflectivity, or spectroscopy is required. For Job ID 1419, demonstrated experience in electrochemical methods or working with molten salts is required. Experience with the chemical and physical properties of materials at high-temperature is highly desirable for both these positions. For Job ID 1564, experience with experimental, time-resolved studies of reaction kinetics and mechanisms is required and experience with pulse radiolysis or laser flash photolysis techniques is highly desirable. ***** *Patty Lee* *Administrative Assistant to * *Lynne E. Ecker, Chair* *Nuclear Science and Technology Department* *Brookhaven National Laboratory* *Building 817* *Upton, New York 11973* *(tel.) 631-344-7040* *(fax) 631-344-3957* *e-mail: patty(a)bnl.gov <patty(a)bnl.gov>*

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Postdoctoral Research Associate positions
by Ecker, Lynne 08 Jan '19

08 Jan '19

Dear Colleagues, We are seeking candidates for postdoctoral Research Associate positions within the Energy Frontier Research Center (EFRC) on Molten Salts in Extreme Environments at Brookhaven National Laboratory. Information about the positions is summarized below and two flyers are attached to this message. We would appreciate you sharing these opportunities with students, postdocs and other contacts. Please contact us if you have questions. Best regards, Lynne E. Ecker, Chair Nuclear Science and Technology Department Brookhaven National Laboratory Tel: (631) 344-2538 Email: lecker(a)bnl.gov<mailto:lecker@bnl.gov> James Wishart, Director, Molten Salts in Extreme Environments EFRC Brookhaven National Laboratory Tel: (631) 344-4327 Email: wishart(a)bnl.gov<mailto:wishart@bnl.gov> ***** The Energy Frontier Research Center on Molten Salts in Extreme Environments (EFRC/MSEE) at Brookhaven National Laboratory (BNL) is pleased to announce that we are hiring Postdoctoral Research Associates. These positions will be part of a collaborative, multi-institution team performing electrochemical, structural (x-ray and neutron), spectroscopic (optical and x-ray), kinetics, and computational studies of molten salt and solute structure, speciation and reactivity in the bulk and at interfaces. The MSEE Center's scientific mission is to provide fundamental, atomic-level understanding of bulk and interfacial molten salts, and the effects of molten salt exposure on interfaces, in support of their use in molten salt nuclear reactors. To this end, we are developing novel in-situ synchrotron, electrochemical and electron microscopy techniques for investigating high-temperature molten salts. Two positions require a Ph.D. degree in chemistry, physics, materials science or a related field. The interdisciplinary research will focus on structural, spectroscopic, and electrochemical investigations of molten salts, solutes in them, and liquid-solid interfaces. A third position requires a Ph.D. degree in chemistry or a related field and primarily involves pulse radiolysis investigations of reaction kinetics in molten salts, in pure form and in mixtures containing other salts and metal ions. To find detailed descriptions of the position requirements and apply online, go to https://jobs.bnl.gov and search for "molten salts." For Job ID 1411, hands-on experience in either X-ray diffraction, reflectivity, or spectroscopy is required. For Job ID 1419, demonstrated experience in electrochemical methods or working with molten salts is required. Experience with the chemical and physical properties of materials at high-temperature is highly desirable for both these positions. For Job ID 1564, experience with experimental, time-resolved studies of reaction kinetics and mechanisms is required and experience with pulse radiolysis or laser flash photolysis techniques is highly desirable. ***** Patty Lee Administrative Assistant to Lynne E. Ecker, Chair Nuclear Science and Technology Department Brookhaven National Laboratory Building 817 Upton, New York 11973 (tel.) 631-344-7040 (fax) 631-344-3957 e-mail: patty(a)bnl.gov<mailto:patty@bnl.gov>

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