镁的同位素
镁（原子量：24.3050(6)）共有22个已知同位素，质量数介于19-40之间，其中有3个是稳定的，其他都具有放射性。天然存在的镁同位素有3个，分别是24Mg、25Mg、26Mg，皆为稳定同位素。其他放射性同位素都不出现在自然界中，只有在实验室制造出来过，且半衰期都很短，非常不稳定，其中最长寿的是28Mg，半衰期为20.915小时。
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| 标准原子质量 (Ar, 标准) |
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图表 编辑
| 符号 | Z（ p ） |
N（ n ） |
同位素质量（u） | 半衰期 | 衰变 方式[2] |
衰变 产物[n 1] |
原子核 自旋 |
相对丰度 （莫耳分率） |
相对丰度的变化量 （莫耳分率） |
|---|---|---|---|---|---|---|---|---|---|
| 18Mg[3] | 12 | 6 | 2p | 16Ne | 0+ | ||||
| 19Mg | 12 | 7 | 19.03417(5) | 5(3) ps | 2p | 17Ne | 1/2−# | ||
| 20Mg | 12 | 8 | 20.018863(29) | 90.8(24) ms | β+ (97%) | 20Na | 0+ | ||
| β+, p (3%) | 19Ne | ||||||||
| 21Mg | 12 | 9 | 21.011713(18) | 122(2) ms | β+ (66.9%) | 21Na | (5/2,3/2)+ | ||
| β+, p (32.6%) | 20Ne | ||||||||
| β+, α (0.5%) | 17F | ||||||||
| 22Mg | 12 | 10 | 21.9995738(14) | 3.8755(12) s | β+ | 22Na | 0+ | ||
| 23Mg | 12 | 11 | 22.9941237(14) | 11.317(11) s | β+ | 23Na | 3/2+ | ||
| 24 Mg |
12 | 12 | 23.985041700(14) | 稳定 | 0+ | 0.7899(4) | 0.78958–0.79017 | ||
| 25Mg | 12 | 13 | 24.98583692(3) | 稳定 | 5/2+ | 0.1000(1) | 0.09996–0.10012 | ||
| 26Mg[n 2] | 12 | 14 | 25.982592929(30) | 稳定 | 0+ | 0.1101(3) | 0.10987–0.11030 | ||
| 27Mg | 12 | 15 | 26.98434059(5) | 9.458(12) min | β− | 27Al | 1/2+ | ||
| 28Mg | 12 | 16 | 27.9838768(22) | 20.915(9) h | β− | 28Al | 0+ | ||
| 29Mg | 12 | 17 | 28.988600(15) | 1.30(12) s | β− | 29Al | 3/2+ | ||
| 30Mg | 12 | 18 | 29.990434(9) | 335(17) ms | β− (99.94%) | 30Al | 0+ | ||
| β−, n (.06%) | 29Al | ||||||||
| 31Mg | 12 | 19 | 30.996546(13) | 230(20) ms | β− (98.3%) | 31Al | 3/2+ | ||
| β−, n (1.7%) | 30Al | ||||||||
| 32Mg | 12 | 20 | 31.998975(19) | 86(5) ms | β− (97.6%) | 32Al | 0+ | ||
| β−, n (2.4%) | 31Al | ||||||||
| 33Mg | 12 | 21 | 33.005254(21) | 90.5(16) ms | β− (83%) | 33Al | 7/2−# | ||
| β−, n (17%) | 32Al | ||||||||
| 34Mg | 12 | 22 | 34.00946(25) | 20(10) ms | β− (>99.9%) | 34Al | 0+ | ||
| β−, n (<.1%) | 33Al | ||||||||
| 35Mg | 12 | 23 | 35.01734(43)# | 70(40) ms | β−, n (52%) | 34Al | (7/2−)# | ||
| β− (48%) | 35Al | ||||||||
| 36Mg | 12 | 24 | 36.02300(54)# | 3.9(13) ms | β− | 36Al | 0+ | ||
| 37Mg | 12 | 25 | 37.03140(97)# | 40# ms [>260 ns] | β− | 37Al | 7/2−# | ||
| β−, n | 36Al | ||||||||
| 38Mg | 12 | 26 | 38.03757(54)# | 1# ms [>260 ns] | 0+ | ||||
| 39Mg | 12 | 27 | 39.04677(55)# | <260 ns | 7/2−# | ||||
| 40Mg | 12 | 28 | 40.05393(97)# | 1# ms | 0+ | ||||
备注：画上#号的数据代表没有经过实验的证明，只是理论推测而已，而用括号括起来的代表数据不确定性。
| ← | 同位素列表 | → |
| 钠的同位素 | 镁的同位素 | 铝的同位素 |
注释 编辑
参考文献 编辑
- ^ Meija, Juris; et al. Atomic weights of the elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry. 2016, 88 (3): 265–91. doi:10.1515/pac-2015-0305.
- ^ Universal Nuclide Chart. nucleonica. [2015-09-10]. （原始内容
存档于2017-02-19）.
- ^ Jin, Y.; et al. First observation of the four-proton unbound nucleus 18Mg. Physical Review Letters. 2021, 127 (262502). doi:10.1103/PhysRevLett.127.262502.
- 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) （页面存档备份，存于互联网档案馆）. Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005) （页面存档备份，存于互联网档案馆）.
- 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 （页面存档备份，存于互联网档案馆）, Nuc. Phys. A 729, pp. 3-128 (2003).
- National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database （页面存档备份，存于互联网档案馆） (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.