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 = 58.6 h); this is the lightest isotope with a long-lived isomer.

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.

Scandium-44 has potential medical use for PET imaging.

List of isotopes

|-id=Scandium-37 | 37Sc | style="text-align:right" | 21 | style="text-align:right" | 16 | 37.00376(44) | style="text-align:center" | 2024 | | p | 36Ca

|-id=Scandium-38 | 38Sc | style="text-align:right" | 21 | style="text-align:right" | 17 | 37.995002(15) | style="text-align:center" | 2024 | | p | 37Ca

|-id=Scandium-39 | 39Sc | style="text-align:right" | 21 | style="text-align:right" | 18 | 38.984785(26) | style="text-align:center" | 1988 | | p | 38Ca | 7/2−# | |-id=Scandium-40 | rowspan=3|40Sc | rowspan=3 style="text-align:right" | 21 | rowspan=3 style="text-align:right" | 19 | rowspan=3|39.9779673(30) | rowspan=3 style="text-align:center" | 1955 | rowspan=3|182.3(7) ms | β+ (99.54%) | 40Ca | rowspan=3|4− | rowspan=3| |- | β+, p (0.44%) | 39K |- | β+, α (0.017%) | 36Ar |-id=Scandium-41 | 41Sc | style="text-align:right" | 21 | style="text-align:right" | 20 | 40.969251163(83) | style="text-align:center" | 1941 | 596.3(17) ms | β+ | 41Ca | 7/2− | |-id=Scandium-42 | 42Sc | style="text-align:right" | 21 | style="text-align:right" | 21 | 41.96551669(17) | style="text-align:center" | 1955 | 680.72(26) ms | β+ | 42Ca | 0+ | |-id=Scandium-42m | style="text-indent:1em" | 42mSc | colspan="3" style="text-indent:2em" | 616.81(6) keV | style="text-align:center" | 1963 | 61.7(4) s | β+ | 42Ca | 7+ | |-id=Scandium-43 | 43Sc | style="text-align:right" | 21 | style="text-align:right" | 22 | 42.9611504(20) | style="text-align:center" | 1935 | 3.891(12) h | β+ | 43Ca | 7/2− | |-id=Scandium-43m1 | style="text-indent:1em" | 43m1Sc | colspan="3" style="text-indent:2em" | 151.79(8) keV | style="text-align:center" | 1964 | 438(5) μs | IT | 43Sc | 3/2+ | |-id=Scandium-43m2 | style="text-indent:1em" | 43m2Sc | colspan="3" style="text-indent:2em" | 3123.73(15) keV | style="text-align:center" | 1971 | 472(3) ns | IT | 43Sc | 19/2− | |-id=Scandium-44 | 44Sc | style="text-align:right" | 21 | style="text-align:right" | 23 | 43.9594028(19) | style="text-align:center" | 1937 | 4.0421(25) h | β+ | 44Ca | 2+ | |-id=Scandium-44m1 | style="text-indent:1em" | 44m1Sc | colspan="3" style="text-indent:2em" | 67.8679(14) keV | style="text-align:center" | 1959 | 154.8(8) ns | IT | 44Sc | 1− | |-id=Scandium-44m2 | style="text-indent:1em" | 44m2Sc | colspan="3" style="text-indent:2em" | 146.1914(20) keV | style="text-align:center" | 1964 | 51.0(3) μs | IT | 44Sc | 0− | |-id=Scandium-44m3 | rowspan=2 style="text-indent:1em" | 44m3Sc | rowspan=2 colspan="3" style="text-indent:2em" | 271.240(10) keV | rowspan=2 style="text-align:center" | 1938 | rowspan=2|58.61(10) h | IT (98.80%) | 44Sc | rowspan=2| 6+ | rowspan=2| |- | β+ (1.20%) | 44Ca |-id=Scandium-45 | 45Sc | style="text-align:right" | 21 | style="text-align:right" | 24 | 44.95590705(71) | style="text-align:center" | 1923 | colspan=3 align=center|Stable | 7/2− | 1.0000 |-id=Scandium-45m | style="text-indent:1em" | 45mSc | colspan="3" style="text-indent:2em" | 12.40(5) keV | style="text-align:center" | 1964 | 318(7) ms | IT | 45Sc | 3/2+ | |-id=Scandium-46 | 46Sc | style="text-align:right" | 21 | style="text-align:right" | 25 | 45.95516703(72) | style="text-align:center" | 1936 | 83.757(14) d | β− | 46Ti | 4+ | |-id=Scandium-46m1 | style="text-indent:1em" | 46m1Sc | colspan="3" style="text-indent:2em" | 52.011(1) keV | style="text-align:center" | 1968 | 9.4(8) μs | IT | 46Sc | 6+ | |-id=Scandium-46m2 | style="text-indent:1em" | 46m2Sc | colspan="3" style="text-indent:2em" | 142.528(7) keV | style="text-align:center" | 1948 | 18.75(4) s | IT | 46Sc | 1− | |-id=Scandium-47 | 47Sc | style="text-align:right" | 21 | style="text-align:right" | 26 | 46.9524024(21) | style="text-align:center" | 1945 | 3.3492(6) d | β− | 47Ti | 7/2− | |-id=Scandium-47m | style="text-indent:1em" | 47mSc | colspan="3" style="text-indent:2em" | 766.83(9) keV | style="text-align:center" | 1964 | 272(8) ns | IT | 47Sc | (3/2)+ | |-id=Scandium-48 | 48Sc | style="text-align:right" | 21 | style="text-align:right" | 27 | 47.9522229(53) | style="text-align:center" | 1937 | 43.67(9) h | β− | 48Ti | 6+ | |-id=Scandium-49 | 49Sc | style="text-align:right" | 21 | style="text-align:right" | 28 | 48.9500132(24) | style="text-align:center" | 1940 | 57.18(13) min | β− | 49Ti | 7/2− | |-id=Scandium-50 | 50Sc | style="text-align:right" | 21 | style="text-align:right" | 29 | 49.9521874(27) | style="text-align:center" | 1959 | 102.5(5) s | β− | 50Ti | 5+ | |-id=Scandium-50m | rowspan=2 style="text-indent:1em" | 50mSc | rowspan=2 colspan="3" style="text-indent:2em" | 256.895(10) keV | rowspan=2 style="text-align:center" | 1963 | rowspan=2|350(40) ms | IT (>99%) | 50Sc | rowspan=2|2+ | rowspan=2| |- | β− (<1%) | 50Ti |-id=Scandium-51 | 51Sc | style="text-align:right" | 21 | style="text-align:right" | 30 | 50.9535688(27) | style="text-align:center" | 1966 | 12.4(1) s | β− | 51Ti | (7/2)− | |-id=Scandium-52 | 52Sc | style="text-align:right" | 21 | style="text-align:right" | 31 | 51.9564962(33) | style="text-align:center" | 1980 | 8.2(2) s | β− | 52Ti | 3(+) | |-id=Scandium-53 | 53Sc | style="text-align:right" | 21 | style="text-align:right" | 32 | 52.958379(19) | style="text-align:center" | 1980 | 2.4(6) s | β− | 53Ti | (7/2−) | |-id=Scandium-54 | rowspan=2|54Sc | rowspan=2 style="text-align:right" | 21 | rowspan=2 style="text-align:right" | 33 | rowspan=2|53.963029(15) | rowspan=2 style="text-align:center" | 1990 | rowspan=2|526(15) ms | β− (84%) | 54Ti | rowspan=2|(3)+ | rowspan=2| |- | β−, n (16%) | 53Ti |-id=Scandium-54m | style="text-indent:1em" | 54mSc | colspan="3" style="text-indent:2em" | 110.5(3) keV | style="text-align:center" | 1998 | 2.77(2) μs | IT | 54Sc | (5+,4+) | |-id=Scandium-55 | rowspan=2|55Sc | rowspan=2 style="text-align:right" | 21 | rowspan=2 style="text-align:right" | 34 | rowspan=2|54.966890(67) | rowspan=2 style="text-align:center" | 1990 | rowspan=2|96(2) ms | β− (83%) | 55Ti | rowspan=2|(7/2)− | rowspan=2| |- | β−, n (17%) | 54Ti |-id=Scandium-56 | 56Sc | style="text-align:right" | 21 | style="text-align:right" | 35 | 55.97261(28) | style="text-align:center" | 1997 | 26(6) ms | β− | 56Ti | (1+) | |-id=Scandium-56m1 | rowspan=2 style="text-indent:1em" | 56m1ScOrder of ground state and isomer is uncertain. | rowspan=2 colspan="3" style="text-indent:2em" | 0(100)# keV | rowspan=2 style="text-align:center" | 2004 | rowspan=2|75(6) ms | β− (<88%) | 56Ti | rowspan=2|(6+,5+) | rowspan=2| |- | β−, n (>12%) | 55Ti |-id=Scandium-56m2 | style="text-indent:1em" | 56m2Sc | colspan="3" style="text-indent:2em" | 775.0(1) keV | style="text-align:center" | 2010 | 290(17) ns | IT | 56Sc | (4+) | |-id=Scandium-57 | 57Sc | style="text-align:right" | 21 | style="text-align:right" | 36 | 56.97705(19) | style="text-align:center" | 1997 | 22(2) ms | β− | 57Ti | 7/2−# | |-id=Scandium-58 | 58Sc | style="text-align:right" | 21 | style="text-align:right" | 37 | 57.98338(20) | style="text-align:center" | 1997 | 12(5) ms | β− | 58Ti | 3+# | |-id=Scandium-58m1 | style="text-indent:1em" | 58m1Sc | colspan="3" style="text-indent:2em" | 412.5(3) keV | style="text-align:center" | 2021 | 1185(243) ns | IT | 58Sc

|-id=Scandium-58m2 | style="text-indent:1em" | 58m2Sc | colspan="3" style="text-indent:2em" | 1420.7(22) keV | style="text-align:center" | 2020 | 0.60(13) μs | IT | 58Sc

|-id=Scandium-59 | 59Sc | style="text-align:right" | 21 | style="text-align:right" | 38 | 58.98837(27) | style="text-align:center" | 2009 | 12# ms[>620 ns]

| 7/2−# | |-id=Scandium-60 | 60Sc | style="text-align:right" | 21 | style="text-align:right" | 39 | 59.99512(54)# | style="text-align:center" | 2009 | 10# ms[>620 ns]

| 3+# | |-id=Scandium-61 | 61Sc | style="text-align:right" | 21 | style="text-align:right" | 40 | 61.00054(64)# | style="text-align:center" | 2009 | 7# ms[>620 ns]

| 7/2-# | |-id=Scandium-62 | 62Sc | style="text-align:right" | 21 | style="text-align:right" | 41 | 62.00785(64)# | style="text-align:center" | 2018 | 2# ms[>400 ns]

|-id=Scandium-63 | 63Sc | style="text-align:right" | 21 | style="text-align:right" | 42 | 63.01403(75)# | style="text-align:center" | 2025 | 1# ms

| 7/2−#

See also Daughter products other than scandium Isotopes of titanium Isotopes of calcium Isotopes of potassium Isotopes of argon

References