Travel fellowship for US-based based scientists

I would like to pass on word that there are fellowships available for younger scientists based at US institutions (recipients need not be a US citizen) for the IUCr Congress in Montreal this August. Awardees must present their work – either as a poster or talk – at the Congress, and will be expe

open access: Powder Diffraction journal Special Software Issue

I would like to announce that the ICDD and Cambridge Journals have released a special issue of Powder Diffraction (Volume 29 Issue S2) as open access for all of 2015. This is

Re: Help for analysis strain using GSAS？

I am not an expert on strain analysis, but can offer a few comments. The first is that GSAS-II is way better for this than GSAS/EXPGUI for the simple reason that it decouples the instrumental broadening (which should be determined from a standard) from the sample-depended terms (size/microstrain

APS Powder Diffraction Educational Content, APS 100 Years of Powder Diffraction Minisymposium

Due to the wonders of web page management, our web content on powder diffraction, which includes quite a few on-line lectures, has moved to a new location: https://www1.aps.anl.gov/Education/Powder-Diffraction-Educational-Materials. This URL is hard to find at present, so this is worthwhile to

Re: 2-theta shift due to sample displacement in parallel beam

Shay, I have to disagree with much of the previous discussion. Yes, there are aberrations in two-theta with sample displacement in a pseudo-parallel beam instrument and they are different for displacement along the beam direction and for displacement perpendicular to the beam (but in the de

Re: Si Zero-Background Holder Pattern subtraction in GSASII

Have you looked at this: https://subversion.xray.aps.anl.gov/pyGSAS/Tutorials/BkgFit/FitBkgTut.htm, but why is your zero-background plate giving you peaks? It should be off-cut so that there is no Bragg diffraction. Brian On Feb 2, 2018, at 10:09 AM, Muir, Caelin Frederick mailto:cfm...@sandi

Re:

Dear Henk, I am not sure if this is what was intended in your commentary and e-mail, but I read from it the point that have heard often over the years, which is that someone is less than fully deserving of scientific credit because “s/he only developed the software” and in particular the ter

Re: Software re-binned PD data

Tony, These days many if not most powder instruments (~100% of those at synchrotron and neutron sources) do some sort of data processing to take raw measurements and convert them to diffractograms that are used in Rietveld. The key for how to know if this is done properly is to ask if any e

Re: GSAS-II - indexing TOF data

Alex, We do not have a routine that will merge peaks from multiple histograms, but you can use “Save peaks” on each histogram to obtain the files for each. Them manually edit them to create a composite file which can be read in and then used for indexing. Brian On Apr 13, 2020, at 1:24 PM, Al

Re: Computing code for hkl generation

Sure. This can be done in GSAS-II from the GUI (see https://subversion.xray.aps.anl.gov/pyGSAS/Tutorials/Simulation/SimTutorial.htm, just export a HKL file rather than a simulated pattern) or from a Python script (see https://gsas-ii.readthedocs.io/en/latest/GSASIIscriptable.html#pattern-simul

Re: ITO source code

https://subversion.xray.aps.anl.gov/CMPR/trunk/src/ito15/ On Aug 8, 2021, at 6:58 AM, Peter Stephens wrote: Does anybody know where I can find the source code of the powder indexing software ITO? All the best, Peter ** Peter W. Stephens SUNY Distinguished Professor Em

Re: scattering factor for O2- ?

I am going to make the comment that (A) neutral atom form factors are probably closer to the actual electron distribution in most materials where there is significant covalent bonding (~= almost everything) and (B) even if that were not true, the difference between O, O1- and O2- is probably pre

Re: Rietveld condamnation considered as established by some more people

My personal feelings are that regardless of the origin of the idea, Hugo did the work that made crystallographic full pattern fitting possible. That implementation was not just a “programming task” as the minimal capabilities of computers of the day required significant innovation for memory and

Honoring Bob Von Dreele on his 80th

Hi everyone, This December we will celebrate Bob Von Dreele’s 80th birthday with a set of talks and remembrances. This will be held at NIST in Gaithersburg, MD (USA) on Monday, December 4. We welcome talks on Bob’s contributions to science and data analysis, talks on work done cooperatively w