Naturally-occurring scandium (21Sc) is composed of one stable isotope, 45Sc. Twenty-six radioisotopes have been characterized from 37Sc to 63Sc, with the most stable being 46Sc with a half-life of 83.76 days, 47Sc with a half-life of 3.3492 days, 48Sc at 43.67 hours, 44Sc at 4.042 hours, and 43Sc at 3.891 hours. All other radioisotopes isotopes have half-lives shorter than an hour, and the majority of these shorter than 15 seconds. This element also has 13 meta states with the most stable being 44m3Sc (t1/2 = 58.6h); this is the lightest isotope with a long-lived isomer.
↑()– Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
↑#– Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
12#– Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
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