Isotopes of zinc
Naturally occurring zinc (Zn) is composed of the 5 stable isotopes 64Zn, 66Zn, 67Zn, 68Zn, and 70Zn with 64Zn being the most abundant (48.6% natural abundance). Twenty-one radioisotopes have been characterised with the most abundant and stable being 65Zn with a half-life of 244.26 days, and 72Zn with a half-life of 46.5 hours. All of the remaining radioactive isotopes have half-lives that are less than 14 hours and the majority of these have half lives that are less than 1 second. This element also has 4 meta states.
Zinc has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of isotopically enriched 64Zn, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope Zn-65 with a half-life of 244 days and produce approximately 2.27 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several days. Such a weapon is not known to have ever been built, tested, or used.
Standard atomic mass: 65.409(4) 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 | |||||||
| 54Zn | 30 | 24 | 53.99295(43)# | 0+ | |||
| 55Zn | 30 | 25 | 54.98398(27)# | 20# ms [>1.6 µs] | 5/2-# | ||
| 56Zn | 30 | 26 | 55.97238(28)# | 36(10) ms | 0+ | ||
| 57Zn | 30 | 27 | 56.96479(11)# | 38(4) ms | 7/2-# | ||
| 58Zn | 30 | 28 | 57.95459(5) | 84(9) ms | 0+ | ||
| 59Zn | 30 | 29 | 58.94926(4) | 182.0(18) ms | 3/2- | ||
| 60Zn | 30 | 30 | 59.941827(11) | 2.38(5) min | 0+ | ||
| 61Zn | 30 | 31 | 60.939511(17) | 89.1(2) s | 3/2- | ||
| 61m1Zn | 88.4(1) keV | <430 ms | 1/2- | ||||
| 61m2Zn | 418.10(15) keV | 140(70) ms | 3/2- | ||||
| 61m3Zn | 756.02(18) keV | <130 ms | 5/2- | ||||
| 62Zn | 30 | 32 | 61.934330(11) | 9.186(13) h | 0+ | ||
| 63Zn | 30 | 33 | 62.9332116(17) | 38.47(5) min | 3/2- | ||
| 64Zn | 30 | 34 | 63.9291422(7) | STABLE [>2.3E+18 a] | 0+ | 0.48268(321) | |
| 65Zn | 30 | 35 | 64.9292410(7) | 243.66(9) d | 5/2- | ||
| 65mZn | 53.928(10) keV | 1.6(6) µs | (1/2)- | ||||
| 66Zn | 30 | 36 | 65.9260334(10) | STABLE | 0+ | 0.27975(77) | |
| 67Zn | 30 | 37 | 66.9271273(10) | STABLE | 5/2- | 0.04102(21) | |
| 68Zn | 30 | 38 | 67.9248442(10) | STABLE | 0+ | 0.19024(123) | |
| 69Zn | 30 | 39 | 68.9265503(10) | 56.4(9) min | 1/2- | ||
| 69mZn | 438.636(18) keV | 13.76(2) h | 9/2+ | ||||
| 70Zn | 30 | 40 | 69.9253193(21) | STABLE [>1.3E+16 a] | 0+ | 0.00631(9) | |
| 71Zn | 30 | 41 | 70.927722(11) | 2.45(10) min | 1/2- | ||
| 71mZn | 157.7(13) keV | 3.96(5) h | 9/2+ | ||||
| 72Zn | 30 | 42 | 71.926858(7) | 46.5(1) h | 0+ | ||
| 73Zn | 30 | 43 | 72.92978(4) | 23.5(10) s | (1/2)- | ||
| 73m1Zn | 195.5(2) keV | 13.0(2) ms | (5/2+) | ||||
| 73m2Zn | 237.6(20) keV | 5.8(8) s | (7/2+) | ||||
| 74Zn | 30 | 44 | 73.92946(5) | 95.6(12) s | 0+ | ||
| 75Zn | 30 | 45 | 74.93294(8) | 10.2(2) s | (7/2+)# | ||
| 76Zn | 30 | 46 | 75.93329(9) | 5.7(3) s | 0+ | ||
| 77Zn | 30 | 47 | 76.93696(13) | 2.08(5) s | (7/2+)# | ||
| 77mZn | 772.39(12) keV | 1.05(10) s | 1/2-# | ||||
| 78Zn | 30 | 48 | 77.93844(10) | 1.47(15) s | 0+ | ||
| 78mZn | 2673(1) keV | 319(9) ns | (8+) | ||||
| 79Zn | 30 | 49 | 78.94265(28)# | 0.995(19) s | (9/2+) | ||
| 80Zn | 30 | 50 | 79.94434(18) | 545(16) ms | 0+ | ||
| 81Zn | 30 | 51 | 80.95048(32)# | 290(50) ms | 5/2+# | ||
| 82Zn | 30 | 52 | 81.95442(54)# | 100# ms [>300 ns] | 0+ | ||
| 83Zn | 30 | 53 | 82.96103(54)# | 80# ms [>300 ns] | 5/2+# | ||
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.