Isotopes of scandium
Naturally occurring scandium (Sc) is composed of 1 stable isotope 45Sc. 13 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. All of the remaining radioactive isotopes have half lives that are less than 4 hours, and the majority of these have half-lives that are less than 2 minutes. This element also has 100 meta states with the most stable being 44mSc (t½ 58.6 h).
The isotopes of scandium range in atomic weight from 40 u (40Sc) to 54 u (54Sc). The primary decay mode at masses lower than the only stable isotope, 45Sc, is electron capture, and the primary mode at masses above it is beta emission. The primary decay products at atomic weights below 45Sc are calcium isotopes and the primary products from higher atomic weights are titanium isotopes.
Standard atomic mass: 44.955912(6) u
Table
nuclide symbol |
Z(p) | N(n) | isotopic mass (u) |
half-life | nuclear spin |
representative isotopic composition (mole fraction) |
range of natural variation (mole fraction) |
---|---|---|---|---|---|---|---|
excitation energy | |||||||
36Sc | 21 | 15 | 36.01492(54)# | ||||
37Sc | 21 | 16 | 37.00305(32)# | 7/2-# | |||
38Sc | 21 | 17 | 37.99470(32)# | <300 ns | (2-)# | ||
39Sc | 21 | 18 | 38.984790(26) | <300 ns | (7/2-)# | ||
40Sc | 21 | 19 | 39.977967(3) | 182.3(7) ms | 4- | ||
41Sc | 21 | 20 | 40.96925113(24) | 596.3(17) ms | 7/2- | ||
42Sc | 21 | 21 | 41.96551643(29) | 681.3(7) ms | 0+ | ||
42mSc | 616.28(6) keV | 61.7(4) s | (7,5,6)+ | ||||
43Sc | 21 | 22 | 42.9611507(20) | 3.891(12) h | 7/2- | ||
43m1Sc | 151.4(2) keV | 438(7) µs | 3/2+ | ||||
43m2Sc | 3123.2(3) keV | 470(4) ns | (19/2)- | ||||
44Sc | 21 | 23 | 43.9594028(19) | 3.97(4) h | 2+ | ||
44m1Sc | 67.8680(14) keV | 154.2(8) ns | 1- | ||||
44m2Sc | 270.95(20) keV | 58.61(10) h | 6+ | ||||
44m3Sc | 146.224(22) keV | 50.4(7) µs | 0- | ||||
45Sc | 21 | 24 | 44.9559119(9) | STABLE | 7/2- | 1.0000 | |
45mSc | 12.40(5) keV | 318(7) ms | 3/2+ | ||||
46Sc | 21 | 25 | 45.9551719(9) | 83.79(4) d | 4+ | ||
46m1Sc | 52.011(1) keV | 9.4(8) µs | 6+ | ||||
46m2Sc | 142.528(7) keV | 18.75(4) s | 1- | ||||
47Sc | 21 | 26 | 46.9524075(22) | 3.3492(6) d | 7/2- | ||
47mSc | 766.83(9) keV | 272(8) ns | (3/2)+ | ||||
48Sc | 21 | 27 | 47.952231(6) | 43.67(9) h | 6+ | ||
49Sc | 21 | 28 | 48.950024(4) | 57.2(2) min | 7/2- | ||
50Sc | 21 | 29 | 49.952188(17) | 102.5(5) s | 5+ | ||
50mSc | 256.895(10) keV | 350(40) ms | 2+,3+ | ||||
51Sc | 21 | 30 | 50.953603(22) | 12.4(1) s | (7/2)- | ||
52Sc | 21 | 31 | 51.95668(21) | 8.2(2) s | 3(+) | ||
53Sc | 21 | 32 | 52.95961(32)# | >3 s | (7/2-)# | ||
54Sc | 21 | 33 | 53.96326(40) | 260(30) ms | 3+# | ||
54mSc | 110(3) keV | 7(5) µs | (5+) | ||||
55Sc | 21 | 34 | 54.96824(79) | 0.115(15) s | 7/2-# | ||
56Sc | 21 | 35 | 55.97287(75)# | 35(5) ms | (1+) | ||
57Sc | 21 | 36 | 56.97779(75)# | 13(4) ms | 7/2-# | ||
58Sc | 21 | 37 | 57.98371(86)# | 12(5) ms | (3+)# | ||
59Sc | 21 | 38 | 58.98922(97)# | 10# ms | 7/2-# | ||
60Sc | 21 | 39 | 59.99571(97)# | 3# ms | 3+# |
Notes
- Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
- Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.
References
- Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
- Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report). Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005).
- Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
- Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties, Nuc. Phys. A 729, pp. 3-128 (2003).
- National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database (retrieved Sept. 2005).
- David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.