Talk:Technetium

I found disputes in which isotope(s) of technetium were discovered first. Is it ^95mTc and ^97mTc^[1], or ⁹⁹Tc^[2]? Either way, ⁹⁷Tc and ⁹⁹Tc in the article isotopes of technetium, and ^95mTc and ⁹⁷Tc in the article technetium are incorrect. Nucleus hydro elemon (talk) 08:00, 15 April 2024 (UTC)

The latter reference, given its purpose, should normally be considered the better source for isotope discoveries. But it this case it is complicated, and probably both are right. I wouldn't make a final decision before looking at the original papers from the 1930s, which are paywalled. But here's what seems to be the truth: the first samples of Tc worked with had been made by irradiation of natural molybdenum by protons or deuterons, and were no doubt a mixture of isotopes. Identification as a new element was made by its chemical properties, so the mixture did not matter. It is likely that the first half-lives to be measured were those of 95m and 97m given their value, but the first definite identification of any activity with a mass number was 99m, whose decay by IT allowed the long-lived ground state 99 to be inferred (Thoennessen's compilations do not distinguish isomers). I may change those for now until someone is able to look at those papers and decide the most appropriate wording. 2601:441:8500:B870:DC98:AD98:BDF9:4D9B (talk) 03:51, 16 June 2025 (UTC)