Isotopes of scandium
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Standard atomic weight Ar°(Sc) | ||||||||||||||||||||||||||||||||||||||||||||||
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Naturally occurring scandium (21Sc) is composed of one stable isotope, 45Sc. Twenty-seven radioisotopes have been characterized, with the most stable being 46Sc with a half-life of 83.8 days, 47Sc with a half-life of 3.35 days, and 48Sc with a half-life of 43.7 hours and 44Sc with a half-life of 3.97 hours. All the remaining isotopes have half-lives that are less than four hours, and the majority of these have half-lives that are less than two minutes, the least stable being proton unbound 39Sc with a half-life shorter than 300 nanoseconds. This element also has 13 meta states with the most stable being 44m2Sc (t1/2 58.6 h).
The isotopes of scandium range from 37Sc to 62Sc. The primary decay mode at masses lower than the only stable isotope, 45Sc, is beta-plus or electron capture, and the primary mode at masses above it is beta-minus. The primary decay products at atomic weights below 45Sc are calcium isotopes and the primary products from higher atomic weights are titanium isotopes.
List of isotopes
[edit]
Nuclide [n 1] |
Z | N | Isotopic mass (Da)[4] [n 2][n 3] |
Half-life[1] [n 4] |
Decay mode[1] [n 5] |
Daughter isotope [n 6] |
Spin and parity[1] [n 7][n 4] |
Isotopic abundance | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Excitation energy | |||||||||||||||||||
37Sc[5] | 21 | 16 | 37.00376(44) | p | 36Ca | ||||||||||||||
38Sc[5] | 21 | 17 | 37.995002(15) | p | 37Ca | ||||||||||||||
39Sc | 21 | 18 | 38.984785(26) | p | 38Ca | 7/2−# | |||||||||||||
40Sc | 21 | 19 | 39.9779673(30) | 182.3(7) ms | β+ (99.54%) | 40Ca | 4− | ||||||||||||
β+, p (0.44%) | 39K | ||||||||||||||||||
β+, α (0.017%) | 36Ar | ||||||||||||||||||
41Sc | 21 | 20 | 40.969251163(83) | 596.3(17) ms | β+ | 41Ca | 7/2− | ||||||||||||
42Sc | 21 | 21 | 41.96551669(17) | 680.72(26) ms | β+ | 42Ca | 0+ | ||||||||||||
42mSc | 616.81(6) keV | 61.7(4) s | β+ | 42Ca | 7+ | ||||||||||||||
43Sc | 21 | 22 | 42.9611504(20) | 3.891(12) h | β+ | 43Ca | 7/2− | ||||||||||||
43m1Sc | 151.79(8) keV | 438(5) μs | IT | 43Sc | 3/2+ | ||||||||||||||
43m2Sc | 3123.73(15) keV | 472(3) ns | IT | 43Sc | 19/2− | ||||||||||||||
44Sc | 21 | 23 | 43.9594028(19) | 4.0421(25) h | β+ | 44Ca | 2+ | ||||||||||||
44m1Sc | 67.8679(14) keV | 154.8(8) ns | IT | 44Sc | 1− | ||||||||||||||
44m2Sc | 146.1914(20) keV | 51.0(3) μs | IT | 44Sc | 0− | ||||||||||||||
44m3Sc | 271.240(10) keV | 58.61(10) h | IT (98.80%) | 44Sc | 6+ | ||||||||||||||
β+ (1.20%) | 44Ca | ||||||||||||||||||
45Sc | 21 | 24 | 44.95590705(71) | Stable | 7/2− | 1.0000 | |||||||||||||
45mSc | 12.40(5) keV | 318(7) ms | IT | 45Sc | 3/2+ | ||||||||||||||
46Sc | 21 | 25 | 45.95516703(72) | 83.757(14) d | β− | 46Ti | 4+ | ||||||||||||
46m1Sc | 52.011(1) keV | 9.4(8) μs | IT | 46Sc | 6+ | ||||||||||||||
46m2Sc | 142.528(7) keV | 18.75(4) s | IT | 46Sc | 1− | ||||||||||||||
47Sc | 21 | 26 | 46.9524024(21) | 3.3492(6) d | β− | 47Ti | 7/2− | ||||||||||||
47mSc | 766.83(9) keV | 272(8) ns | IT | 47Sc | (3/2)+ | ||||||||||||||
48Sc | 21 | 27 | 47.9522229(53) | 43.67(9) h | β− | 48Ti | 6+ | ||||||||||||
49Sc | 21 | 28 | 48.9500132(24) | 57.18(13) min | β− | 49Ti | 7/2− | ||||||||||||
50Sc | 21 | 29 | 49.9521874(27) | 102.5(5) s | β− | 50Ti | 5+ | ||||||||||||
50mSc | 256.895(10) keV | 350(40) ms | IT (>99%) | 50Sc | 2+ | ||||||||||||||
β− (<1%) | 50Ti | ||||||||||||||||||
51Sc | 21 | 30 | 50.9535688(27) | 12.4(1) s | β− | 51Ti | (7/2)− | ||||||||||||
β−, n? | 50Ti | ||||||||||||||||||
52Sc | 21 | 31 | 51.9564962(33) | 8.2(2) s | β− | 52Ti | 3(+) | ||||||||||||
β−, n? | 51Ti | ||||||||||||||||||
53Sc | 21 | 32 | 52.958379(19) | 2.4(6) s | β− | 53Ti | (7/2−) | ||||||||||||
β−, n? | 52Ti | ||||||||||||||||||
54Sc | 21 | 33 | 53.963029(15) | 526(15) ms | β− (84%) | 54Ti | (3)+ | ||||||||||||
β−, n (16%) | 53Ti | ||||||||||||||||||
54mSc | 110.5(3) keV | 2.77(2) μs | IT | 54Sc | (5+,4+) | ||||||||||||||
55Sc | 21 | 34 | 54.966890(67) | 96(2) ms | β− (83%) | 55Ti | (7/2)− | ||||||||||||
β−, n (17%) | 54Ti | ||||||||||||||||||
β−, 2n? | 53Ti | ||||||||||||||||||
56Sc | 21 | 35 | 55.97261(28) | 26(6) ms | β− | 56Ti | (1+) | ||||||||||||
β−, n? | 55Ti | ||||||||||||||||||
β−, 2n? | 54Ti | ||||||||||||||||||
56m1Sc[n 8] | 0(100)# keV | 75(6) ms | β− (<88%) | 56Ti | (6+,5+) | ||||||||||||||
β−, n (>12%) | 55Ti | ||||||||||||||||||
β−, 2n? | 54Ti | ||||||||||||||||||
56m2Sc | 775.0(1) keV | 290(17) ns | IT | 56Sc | (4+) | ||||||||||||||
57Sc | 21 | 36 | 56.97705(19) | 22(2) ms | β− | 57Ti | 7/2−# | ||||||||||||
β−, n? | 56Ti | ||||||||||||||||||
β−, 2n? | 55Ti | ||||||||||||||||||
58Sc | 21 | 37 | 57.98338(20) | 12(5) ms | β− | 58Ti | 3+# | ||||||||||||
β−, n? | 57Ti | ||||||||||||||||||
β−, 2n? | 56Ti | ||||||||||||||||||
58mSc | 1420.7(22) keV | 0.60(13) μs | IT | 58Sc | |||||||||||||||
59Sc | 21 | 38 | 58.98837(27) | 12# ms [>620 ns] |
β−? | 59Ti | 7/2−# | ||||||||||||
β−, n? | 58Ti | ||||||||||||||||||
β−, 2n? | 57Ti | ||||||||||||||||||
60Sc | 21 | 39 | 59.99512(54)# | 10# ms [>620 ns] |
β− | 60Ti? | 3+# | ||||||||||||
β−, n? | 59Ti | ||||||||||||||||||
β−, 2n? | 58Ti | ||||||||||||||||||
61Sc | 21 | 40 | 61.00054(64)# | 7# ms [>620 ns] |
β−? | 61Ti | 7/2-# | ||||||||||||
β−, n? | 60Ti | ||||||||||||||||||
β−, 2n? | 59Ti | ||||||||||||||||||
62Sc | 21 | 41 | 62.00785(64)# | 2# ms [>400 ns] |
β−? | 62Ti | |||||||||||||
β−, n? | 61Ti | ||||||||||||||||||
β−, 2n? | 60Ti | ||||||||||||||||||
This table header & footer: |
- ^ mSc – Excited nuclear 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).
- ^ a b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
- ^
Modes of decay:
IT: Isomeric transition n: Neutron emission p: Proton emission - ^ Bold symbol as daughter – Daughter product is stable.
- ^ ( ) spin value – Indicates spin with weak assignment arguments.
- ^ Order of ground state and isomer is uncertain.
References
[edit]- ^ a b c d Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
- ^ "Standard Atomic Weights: Scandium". CIAAW. 2021.
- ^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
- ^ Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf.
- ^ a b Dronchi, N.; Charity, R. J.; Sobotka, L. G.; Brown, B. A.; Weisshaar, D.; Gade, A.; Brown, K. W.; Reviol, W.; Bazin, D.; Farris, P. J.; Hill, A. M.; Li, J.; Longfellow, B.; Rhodes, D.; Paneru, S. N.; Gillespie, S. A.; Anthony, A. K.; Rubino, E.; Biswas, S. (2024-09-12). "Evolution of shell gaps in the neutron-poor calcium region from invariant-mass spectroscopy of 37,38Sc, 35Ca, and 34K". Physical Review C. 110 (3). doi:10.1103/PhysRevC.110.L031302. ISSN 2469-9985.
- Audi, G.; Kondev, F.G.; Wang, M.; Huang, W.J.; Naimi, S. (2017). "The NUBASE2016 evaluation of nuclear properties" (PDF). Chinese Physics C. 41 (3): 030001. doi:10.1088/1674-1137/41/3/030001.
- Isotope masses from:
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- Half-life, spin, and isomer data selected from the following sources.
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.
- Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.