Talk:X-ray crystallography#Split x-ray diffraction and crystallography

{{Wikipedia:Good article reassessment/X-ray crystallography/1}}

I removed a paragraph that cited an error made 32 years ago, due to technical limits in the software and hardware, which no longer exist. These limits were overcome before Wikipedia was initiated. No where else does this article cite papers that were wrong due to limits in the technology at the time the work was done. Nick Beeson (talk) 20:07, 25 October 2023 (UTC)

:While obviously science is self-correcting (we hope) and we don't use our own editorial interest to highlight old mistakes, this specific mistake has itself been covered as a highlight of what happened and why. Therefore I think it is quite WP:DUE to mention it. See for example doi:10.1002/anie.200460864. DMacks (talk) 03:17, 26 October 2023 (UTC)

::For clarity, we're talking about Special:Diff/1181882695 (and the later Special:Diff/1188605822) here. I am not quite able do anything useful right now, but I do feel like talking about some problems is useful. I don't immediately recall anything recent about small-ish molecules like in the 32-year-old case, but it does remind me of a previously-unknown post-translation modification being missed despite visible density (doi:10.1038/s41589-021-00966-5).

::...whether a mention like this is good for GA assessment purposes (length) is beyond the current capabilities of my head. Artoria2e5 🌉 11:22, 15 December 2023 (UTC)

:::For a GA reassment what is needed first is references (sources), as way too much has none. Can you help? Ldm1954 (talk) 17:16, 15 December 2023 (UTC)

The last sentence of Thomson scattering links this page with an unreferenced claim: "X-ray crystallography is based on Thomson scattering.". Maybe someone here has a reference handy that could be added? Even better would be another sentence explaining why. Johnjbarton (talk) 18:06, 30 November 2023 (UTC)

The section on #Contributions of women to x-ray crystallography came originally from Crystallography. It seems more appropriate here, although parts (e.g. international tables) could be in both. Ldm1954 (talk) 19:27, 6 December 2023 (UTC)

The two are not the same, and there are many areas of XRD where the focus is not on detailed determination of atomic positions. Examples are powder diffraction where comparison is made to known samples, SAXS and many more. There are many areas/pages where it is relevant to say "use XRD" but wrong to say use "X-ray crystallography". I am posting here for comment before doing it. Ldm1954 (talk) 07:35, 14 April 2024 (UTC)

:Thanks for posting the question. It might be better then to change the name of the article to X-Ray Diffraction, and then X-ray crystallography becomes a major heading within it. It's just misnamed. Martino3 (talk) 04:24, 18 April 2024 (UTC)

::The current article has stacks on structure determination, which is I argue is "X-ray crystallography" so should stay there. Then XRD can be cleaner Bragg/Kinematical with a bit on dynamical, SXRD and perhaps small angle and soft/white diffraction etc. Plenty there that is not crystallography. Yes? Ldm1954 (talk) 04:30, 18 April 2024 (UTC)

:::Perhaps approaching this from the reverse direction would help clarify the possibilities: reorg this article to more clearly identify the XRD content. In other words, the current article looks like x-ray crystallography with some muddiness from XRD, but if the XRD part were clearer then it would look like two articles that should be split. Johnjbarton (talk) 15:03, 18 April 2024 (UTC)

::::We have an existing powder diffraction article that seems quite detailed and includes X-ray as well as other types of radiation, and a few other diffraction-related articles. I like Johnjbarton's idea of keeping this X-ray crystallography article on its named topic and working on moving content not strictly on that topic to other articles (maybe even new ones). Maybe a start would be X-ray diffraction as a WP:SUMMARYSTYLE parent of powder diffraction, X-ray crystallography, X-ray scattering techniques (which itself is a parent of SAXS, WAXS, etc.), etc. That could help us find better homes for content here that is not on this article's narrowed topic. DMacks (talk) 15:42, 18 April 2024 (UTC)

:::::For DMacks mainly, X-ray scattering is (and should remain) the overall summary as it includes both elastic and inelastic. X-ray crystallography is all about solving, PXRD is different (and I know ICDD want to rewrite that page). Small steps to clean a massive area.

:::::As a very rough guide, see User:Ldm1954/Sandbox/XRD for what would be removed from this article and form the core of an XRD page. Very rough Ldm1954 (talk) 03:35, 19 April 2024 (UTC)

:I am reviving X-ray diffraction (as stated on the crystallography page as well as here and a couple of other places for discussion some time ago), moving selected material from X-ray crystallography, where contributors can be found. More work is needed, this is just the first pass. Ldm1954 (talk) 07:59, 1 May 2024 (UTC)

::

::I suspect that they are used, often enough, synonymously, even if technically they should not be. For one, it is still crystallography on amorphous, or non-crystalline solids. Someone once claimed that crystallography is the best path to a Nobel prize, based on statistics of prize winners. On the other hand, it might be that this one is long enough for two articles. It is crystallography if done by a crystallographer, even if not done on crystals. Gah4 (talk) 11:42, 1 May 2024 (UTC)

:::

:::Sorry, as a professional crystallography I need to point out that this is not right. X-ray diffraction is diffraction using X-rays, similar to electron diffraction. X-ray crystallography is crystallography using X-rays, comparable to electron crystallography. Diffraction is an elastic process with photons, matter waves etc. Crystallography is about determining atomic positions, it is not about mineral crystals despite the name.

:::N.B., yes, there have been many nobels in X-ray crystallography, and relatively few (von Laue, the Braggs) for X-ray diffraction,see the list in the article. Ldm1954 (talk) 12:02, 1 May 2024 (UTC)

::::

::::OK, but what do you do with X-ray diffraction other than X-ray crystallography? One of the more amazing things to me, is that the lattice constant of silicon is known to 10 significant digits. Maybe you don't count measuring that as crystallography, though. Gah4 (talk) 19:58, 2 May 2024 (UTC)

:::::Many other uses beyond crystallography, for instance phase identification by comparison, determination of the composition of mixtures, thermal expansion, disorder, phase transitions, texture, orientation, epitaxy..the list is long and there is much more than I have listed. Ldm1954 (talk) 05:48, 3 May 2024 (UTC)