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No, but it is a good idea. I might add it to a future version.

No, it only reports BGMN-specific width parameters (B1 and k2), but not the FWHM. This is because the fundamental parameters approach (FPA) handles the peak profile different than conventional approaches using peak functions. The FWHM is never determined by the FPA.

Yes they are different. The COD from the Profex website can only be used in Profex. QualX offers a different COD for download on their website. Theirs is already indexed.

The radiation spectrum is defined in the *.lam files in the Profex/BGMNwin directory as a set of lorentzian functions. The Cu.lam file is a bit different than the others in that it parameterizes the kbeta intensity. I think there are also Cu files that model the absorption edge. You can create your own lam files once you understand how they work. You will also need to create copies of the matching *.ano and *.mdr files. These are all text files that can be edited in notepad.

Amazing, thank you so mich for your reply! This was far beyond my hopes for an open-source programm, great to see that someone has considered these effects that are common in your average lab sources data. I will go digging into those files then. Schöne Grüße und frohe Feiertage, Michael

No. You can refine your dataset with FullProf using Profex, but the ED maps only work with BGMN. You will have to use the FullProf tool to create the maps.

You can create separate electron density maps for each refined crystalline phase. If this is of any use for your composite material I don't know.

That is a very unusual error. The file afaparm.dat is part of the Profex installation and it should not suddenly disappear or get corrupted. My best guess is that a malware protection is kicking in and deleting or quarantining Profex files. Maybe you can temporarily disable the anti-virus software and reinstall Profex.

I can't identify the issue based on your description. Please go to the support page on the Profex website and follow the instructions for support requests. The procedure ensures that I get enough information to understand the problem.

@@profextutorials2325 thank you! i have managed to fix it by manually editing the background coefficients in the refinement file. Somehow, they are always set to 0. By increasing it to 5 i get a very good result. Is there a way to set the default to 5?

In one of the device repositories (Locations -> Devices) there is a template file for your instrument configuration (*.tpl). You can open it in a text editor and change the value of RU to 5. Or if you delete the RU line, the value will be assigned dynamically during the refinement. After modifying the file, I recommend to save all 4 files for this configuration (*.sav, *.ger, *.geq, *.tpl) in the device repository outside of the Profex program folder. On Windows it is C:\users\<your name>\...), which is also listed in Locations -> Devices. Else you will lose the modified files with the next update.

There is no such configuration bundled with Profex. You need to create a new one. Check out the video tutorial "instrument configurations" for more information.

It means that you are over-refining your dataset. There must be correlating parameters. As long as chi^2 is just a little bit below 1, e.g. 0.97, I wouldn't worry, it seems to be an excellent refinement. But if it goes further below 1, you should reduce the number of refined parameters.

There is no D6 configuration in Profex yet. You need to create a new one. If you want me to help you with it, please go to the support page on the Profex website to find the support email address. Then send me one of your original Brml files to this address. I may be able to find the necessary hardware information in the file. Ideally, send me a scan of the NIST LaB6 standard or something equivalent.

Your chemical restrictions are probably so strict that no phase in the repositories fulfills them.

Yes, you need to add a precise amount of an internal standard (e.g. Zincite) before running the measurement.

@@profextutorials2325 ok. So I need to mix 90 my raw material with 10 zincate. But know I have problem The databased not working. I cannot download the CIF when retrieved from databased

No, Rietveld refinement needs a raw data set for input. Peak integrals are of no use for RR.

You can replace the following line in the control file: LAMBDA=CU with SYNCHROTRON=x.xxxxx Where x.xxxx is the wavelength in nm.

I still haven't figured it out. If someone knows, I'd be interested, too.

@@profextutorials2325 That's a shame. Maybe if there was a way to manually calculate the sizes based on the refined parameters, rather than through GrainSize function, but I'm not even nearly knowledgeable enough to search for that solution.

You start by creating a regular refinement project, as demonstrated in the beginner's videos or in the case studies. The standard phase is refined as a normal phase. Once you get a good fit, you can select "project -> set internal standard" to change to calculation of phase quantities to the internal standard method and run the refinement again. As a result, you get the absolute phase quantities.

One thing that comes to mind is that the calculation of Chi^2 depends on the number of refined parameters. If you release more parameters, Rexp gets a bit smaller, and hence chi^2 = (Rwp/Rexp)^2 increases. Whether or not this explains your observations I don't know. The crystallite size is derived from the peak width. So whatever fits your peak shape better should result in more accurate crystallite sizes. In a high-quality dataset, that would be the structure refinement. But in a low-quality dataset, a structure refinement might over-refine the data and result in bogus results. Without seeing your data I can't tell which of the two scenarios applies to you.

Yes, it affects the peak positions in the same way it does in Rietveld refinement.

It shouldn't be necessary anymore. The app is now code-signed with a certificate on OS X. You may still be asked to give it access to the documents folder. If you messed up your program settings, check out the FAQ to reset everything to default: www.profex-xrd.org/faq/#hfaq-post-1863

Is B1 refined to 0.0? That means infinitely large crystallites, which is reported as GrainSize=ERROR. The physical meaning is "too large to cause any detectable peak broadening".

Indeed Profex doesn't know if the third column is the error or another scan. That's why it opens it as a scan. If your dat file uses a format that is directly supported by the BGMN kernel, you can disable the conversion to xy format by Profex, which discards the error information. Here is what you need to do: 1. Change the file extension of your dat file to xye 2. Go to "Edit -> Preferences -> BGMN -> Backend configuration" and make sure that the line "Do not convert scan files to XY format" contains the extension "xye". Profex may still show the error as a scan at first, but it will feed the file directly to BGMN, which will then use the error correctly. In order for the xye file to be accepted by BGMN, it needs to use space separators and the # comment sign.

@@profextutorials2325 thanks a lot for your kind answer. I tried and indeed Profex recognized the third column, however the Rexp dropped to 0.48, that seems very low also compared to other Rexp from the literature. At this point, even if the fit seems quite good the chi-square is very high. Do you think 0.48 is a possible value for Rexp or I made some mistakes importing/structuring the file?

Make sure that there are no spaces in the code segment (e.g. after the comma or around the minus sign): E=(CA(p),MG(1-p)) If that doesn't solve the issue, please contact me through the support e-mail address given on the Profex website.

Thanks! I fixed the titles.

Your phase is probably not yet in the default repository. In that case, search-match makes no sense. Since you already know what phase it is, you can instead search for it in the COD database (file > import structure files > query COD database). You need to make sure that the COD is installed and connected. There is a video explaining it on this channel.

It's the instrument configuration the sample was measured on. It is important to select a configuration that exactly represents the instrument that was used to acquire the dataset.

Is there something wrong with the existing playlist? ruclips.net/p/PL08rIEwvHHOqb7FsgbIWDuKLXqDyLODPI It looks OK to me. Please let me know if videos are missing or shuffled for you.

While in theory it is possible to add the calculation of bond lengths to the STR files, it is extremely cumbersome. Profex version 5.3 will come with a dialog that lists bond lengths after the refinement.

Thanks. The files are available here (section March 2024): www.profex-xrd.org/lecture-handouts/

If you right-click on the header of the peak list, you can select which parameters are shown in the list.

@@profextutorials2325 And when all the angles appear only 0?

Please follow the instructions for support requests on the Profex website when asking for support.

@@profextutorials2325 Thanks for the orientations

For the record, it's a bug in Profex that occurs with *.xy scan files. It will be fixed in version 5.2.9.

I am not sure why this happens, and I don't have access to the ISCD for verification. Just a guess: relative intensities are instrument-dependent. A fix divergence slit produces different intensities than a variable one. Profex also considers beam overflow when the beam spills over the sample surface at low angles, which also changes the intensities. Maybe that explains your observation.

@@profextutorials2325 Perhaps I didn't convey my message clearly. I mean the hkl plot calculated by Profex is inconsistent with the hkl plot in the ICSD database.

That does not add any information to your previous message. Please follow the instructions for support requests on the Profex website when asking for support.

Sir, in the 13th slide "modelling the peak profile": The software GSAS-II uses instrument configuration approach (because it needs instrument parameters file) and the software Fullprof uses empirical function approach, right?

They will come. I plan to release one every weekend for the coming weeks.

The scale factor is the GEWICHT parameter. It is not the Rietveld scale factor, though, because it is already corrected for the unit cell density: GEWICHT is equivalent to S*(Z*M*V)