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

Re: [Ifeffit] XEOL
by Eugenio Otal 06 Dec '21

06 Dec '21

Dear Robert, sorry for the late reply, life... Brilliant suggestion! I will let you know the results if the proposal is approved. Best regards, euG If you can move between Nd L3 and Br K, why not stop at Nd L1 if you want to see if a Nd s-type initial state has any influence on the XEOL? You should not need to go up to Nd K. Some references: https://aip.scitation.org/doi/abs/10.1063/1.477320?journalCode=jcp https://iopscience.iop.org/article/10.1149/1.3211180 and a book chapter https://www.worldscientific.com/doi/10.1142/9789812775757_0015 On 2021-11-25 5:50 p.m., Eugenio Otal wrote: > Hi all, > I am planning XEOL measurements and I have a doubt. > My system is Nd coordinated to Eosin, tetrabromofluorescein. I want to > measure XEOL exciting on the Br K-edge (13.4keV) and the Nd > L3-edge(6.2keV) and measure the emission spectra of the dye and the > Nd. I just measured the emission of the Nd exciting at 530nm and it > worked perfectly. > My question is, I have access to Nd K-edge, is it worthy?to measure > XEOL at the K-edge? I am in the time limit to?request an?extra shift. > I would appreciate some bibliography. > Best regards. > > _______________________________________________ > 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

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Larch 0.9.57
by Matt Newville 02 Dec '21

02 Dec '21

Hi All, Larch version 0.9.57 has been released and is available on PyPI ( https://pypi.org/project/xraylarch) It should now be installed by default using most installation mechanisms, and you may see a notice to update if running xas_viewer. The updates are described in some at https://github.com/xraypy/xraylarch/releases/tag/0.9.57 and in the github commit history. This includes adding support for reading RIXS data files from ESRF BM16, better support for de-glitching in XAS_Viewer, and fixing of reading of many Athena Project Files that were saved in the "old style" and have non-ASCII characters (the code now correctly reads the 78 Project files at https://github.com/xraypy/xraylarch/tree/master/examples/xafsdata/AthenaPro… ). Much of the work for this release has come from Mauro Rovezzi. In a conversation we had yesterday about this release, we talked about several potential changes going forward, especially for XAS_Viewer, about saving processing history, how to improve the concept of "reference spectrum" for a measurement, and other topics related to keeping track of analysis history and provenance. Some of these ideas are encapsulated in Github Issues at https://github.com/xraypy/xraylarch/issues, and the plan is to work on this. One possibility would be to be able to read and export to Athena Project files but use a different format (probably HDF5) as a new default "Larch Project File" so that more complexly nested data and some sort of "journal" per data set could be saved, displayed, edited, and so on. If anyone here has some thoughts on how such topics could or should be handled, please let us know. If you have other ideas on what might be added or improved, also don't hesitate to speak up, either in conversations here or on Github. Cheers, --Matt Newville

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XEOL
by Eugenio Otal 26 Nov '21

26 Nov '21

Hi all, I am planning XEOL measurements and I have a doubt. My system is Nd coordinated to Eosin, tetrabromofluorescein. I want to measure XEOL exciting on the Br K-edge (13.4keV) and the Nd L3-edge(6.2keV) and measure the emission spectra of the dye and the Nd. I just measured the emission of the Nd exciting at 530nm and it worked perfectly. My question is, I have access to Nd K-edge, is it worthy to measure XEOL at the K-edge? I am in the time limit to request an extra shift. I would appreciate some bibliography. Best regards.

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PostDoc position at Northeastern University
by NUCRET 23 Nov '21

23 Nov '21

Northeastern University Center for Renewable Energy Technology is currently looking for highly qualified candidate to fill a Post-Doctoral Research Associate position with hands-on experience in the area of in situ and operando XAS, XANES, EXAFS spectroscopy, high-energy XRD as applicable to batteries (especially solid-state), fuel cells and electrolyzers. Familiarity with Brookhaven synchrotron facility (or other US-based light source facilities, e.g. ANL, SLAC) is a plus. Candidates should be in the US and authorized to work in the US (visa is _not_ offered). To apply, please use Northeastern University Career Portal: https://careers.hrm.northeastern.edu/cw/en-us/job/508477/postdoctoral-resea…

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Postdoctoral beamline scientist position at Illinois Tech/MRCAT
by Carlo Segre 22 Nov '21

22 Nov '21

Please find attached the advertisement for a postdoctoral position at MRCAT (Sector 10) at the Advanced Photon Source. The position is with Illinois Institute of Technology, which operates MRCAT for its institutional membership. Feel free to share this with any appropriate individuals. Carlo -- Carlo U. Segre (he/him) -- Duchossois Leadership Professor of Physics Professor of Materials Science & Engineering Director, Center for Synchrotron Radiation Research and Instrumentation Illinois Institute of Technology Voice: 312.567.3498 Fax: 312.567.3494 segre(a)iit.edu http://phys.iit.edu/~segre segre(a)debian.org

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SSRL post-doctoral position
by Ritimukta Sarangi 17 Nov '21

17 Nov '21

Hi, I would like to bring this unique opportunity to the EXAFS user community. I am looking to hire a post-doctoral fellow who will apply spectroscopy tools to the Ni-Fe containing active site in Carbon Monoxide dehydrogenase, which is part of a pathway that biologically captures CO2 and converts it into acetate. This project is funded by the Department of Energy and is extremely relevant to our understanding and remediation of CO2 in the atmosphere. You will work with a diverse team of postdocs working on a variety of X-ray spectroscopy projects and will get the experience of working in a national laboratory setting. See the attached posting for more information. Kind regards, Riti Sarangi

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Fe and Ni carbide XAS reference spectra?
by Valentijn De Coster 17 Nov '21

17 Nov '21

Dear ifeffit mailing list, My name is Valentijn De Coster. I am a PhD student at Ghent University, Belgium, working on Ni and Fe materials for CO2 utilization. I am currently looking for Fe and Ni carbide (Fe3C, Ni3C) reference XAS spectra, at the respective Fe K and Ni K edges, for fingerprinting purposes. As such, I was wondering whether anyone would have such data available. On a side note, I checked the CARS database, and while this has an Fe3C (Fe K edge) reference, the data file does not contain the Energy values of the spectrum. Thank you in advance for your time. Kind regards, Valentijn De Coster [Image result for ghent university logo] Valentijn De Coster PhD Student Laboratory for Chemical Technology (LCT) Department of Materials, Textiles and Chemical Engineering Technologiepark 125, 9052 Ghent, Belgium T: +32 9 331 17 M: +32 (0) 331 17 10 https://www.lct.ugent.be<https://www.lct.ugent.be/> https://helpdesk.UGent.be/e-maildisclaimer.php<https://helpdesk.ugent.be/e-maildisclaimer.php> Member of CSC: https://www.csc.ugent.be<https://www.csc.ugent.be/>

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MacPorts XAFS software: announcing a Port for Larch; and do we actually need Demeter on Macs?
by Fowler, Joseph W. (Assoc) 12 Nov '21

12 Nov '21

Hello XAFS fans: This note is about the Demeter package on MacPorts. If you don’t use Demeter through MacPorts on a Mac, skip this note. I’m the MacPorts “maintainer” of the ports demeter and ifeffit. They have been not installable or upgradeable for something like a year, because of new releases of … something? Probably either Mac OS X, and/or Apple's Xcode development system. I’ve made a ton of progress on my big goal of restoring demeter to life, but I cannot get all the way to finish the project. I have to say here that I’m a poor choice to maintain these ports. I barely understand how MacPorts works, and I don’t understand or use Perl at all. I am not even really an x-ray scientist—I develop superconducting x-ray sensors in a team at NIST, and I happened to be a collaborator of the previous maintainer when he left the field 6 or 8 years ago. I worked on the problem in two parallel paths. One was to create an official port for the Python package Larch. Late last month this was complete, so you can do a “sudo port install py39-xraylarch” and have it. (Replace “py39” with “py38” or “py37” if you use Python 3.8/3.7.) This required creating about a dozen new ports for Larch’s dependencies. (Actually, I know a ton more about how MacPorts works than I did six weeks ago.) Some new ports that might be of interest to this community include: * py39-pymatgen * py39-peakutils * py39-xraydb * py39-spglib * py39-xraylarch My other path was to track down and fix the problem that prevented ifeffit from compiling. (Recall that this package is unmaintained since 2014. See https://github.com/newville/ifeffit/) It looks like Xcode’s C compiler recently turned the “implicit function warning” into an error. A few hours ago, MacPorts accepted my proposed patches, so at least ifeffit should be installable as a port again. Unfortunately, demeter still won’t install completely, owing to problems in certain Perl-based ports that it depends upon, like p5.30-wx. That problem is so far from my expertise that I am completely stuck. I had hoped that if I got ifeffit to work, demeter would follow, but I was wrong. There are four strategies I can imagine from here: 1. Declare the ports ifeffit and demeter to be obsolete. Mac users will need to figure out other ways to do what Athena and Artemis do. 2. Wait until Perl experts fix the Perl dependencies (expect it to take months or more), then I fix demeter. 3. Modify/migrate Demeter so that Athena and Artemis rely completely on Larch and not at all on ifeffit. 4. Ask this mailing list for advice. I don’t know what strategy #3 would entail—again, I know zero Perl and don’t use this software. Demeter’s author told me he doesn’t have much interest in this upgrade. All I can really support alone is strategy #1 or #2: obsoleting or waiting. And that’s why I’m writing. On one side, does anyone care if Athena/Artemis become unavailable through MacPorts? So, does anyone object to path #1? On the other, does anyone here have better ideas? Best wishes, Joe Fowler NIST Boulder Labs

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how to learn wavelet analysis
by 罗昕宇 11 Nov '21

11 Nov '21

Dear IFEFFIT members, I'm a fresh graduate student majoring in chemical engineering. I began to learn XAFS by myself one month ago. I bought and read the book XAFS for Everyone written by Dr. Calvin. I think I have got a clear image of how EXAFS works. Recently, I am attracted by the technique called Wavelet Analysis from literatures. It seems pretty powerful to correlate both temporal and frequency information, but something just went probably beyond my current knowledge base. I understand that a changeable window should be adapted to a make a trade-off between time and frequency, but I don't understand the logic that good time-resolution in high frequency is preferred while in low frequency a good frequency-resolution is better. I would appreciate it very much if you could answer my half-baked question and offer me with some learning material. Best regards Xinyu

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iodine L-edge spectra
by Enyuan Hu 27 Oct '21

27 Oct '21

Hi, Does anybody happen to have the iodine element L-edge spectra (L1 preferred, but L2 and L3 are also okay) and is willing to share? thanks! Enyuan

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