（重定向自镭-226）
| ||||||||||||||||||||||||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||
鐳没有稳定或长寿命的同位素，故无法给出它的标准原子量。镭有从202Ra到234Ra共33种同位素，其中最稳定也最常见的同位素是半衰期1600年的226Ra。
2013年发现镭-224的原子核呈梨形，首次发现不对称原子核。[1]
圖表
[编辑]| 符號 | 歷史 名稱 |
Z | N | 同位素質量（u） [n 1][n 2] |
半衰期 [n 2] |
衰變 方式[2] |
衰變 產物 [n 3] |
原子核 自旋[n 1] |
相對豐度 （莫耳分率） |
|---|---|---|---|---|---|---|---|---|---|
| 激發能量[n 1][n 2] | |||||||||
| 202Ra | 88 | 114 | 202.00989(7) | 2.6(21) ms [0.7(+33−3) ms] |
0+ | ||||
| 203Ra | 88 | 115 | 203.00927(9) | 4(3) ms | α | 199Rn | (3/2−) | ||
| β+ （不常見） | 203Fr | ||||||||
| 203mRa | 220(90) keV | 41(17) ms | α | 199Rn | (13/2+) | ||||
| β+ （不常見） | 203Fr | ||||||||
| 204Ra | 88 | 116 | 204.006500(17) | 60(11) ms [59(+12−9) ms] |
α (99.7%) | 200Rn | 0+ | ||
| β+ (.3%) | 204Fr | ||||||||
| 205Ra | 88 | 117 | 205.00627(9) | 220(40) ms [210(+60−40) ms] |
α | 201Rn | (3/2−) | ||
| β+ （不常見） | 205Fr | ||||||||
| 205mRa | 310(110)# keV | 180(50) ms [170(+60−40) ms] |
α | 201Rn | (13/2+) | ||||
| IT （不常見） | 205Ra | ||||||||
| 206Ra | 88 | 118 | 206.003827(19) | 0.24(2) s | α | 202Rn | 0+ | ||
| 207Ra | 88 | 119 | 207.00380(6) | 1.3(2) s | α (90%) | 203Rn | (5/2−,3/2−) | ||
| β+ (10%) | 207Fr | ||||||||
| 207mRa | 560(50) keV | 57(8) ms | IT (85%) | 207Ra | (13/2+) | ||||
| α (15%) | 203Rn | ||||||||
| β+ (.55%) | 207Fr | ||||||||
| 208Ra | 88 | 120 | 208.001840(17) | 1.3(2) s | α (95%) | 204Rn | 0+ | ||
| β+ (5%) | 208Fr | ||||||||
| 208mRa | 1800(200) keV | 270 ns | (8+) | ||||||
| 209Ra | 88 | 121 | 209.00199(5) | 4.6(2) s | α (90%) | 205Rn | 5/2− | ||
| β+ (10%) | 209Fr | ||||||||
| 210Ra | 88 | 122 | 210.000495(16) | 3.7(2) s | α (96%) | 206Rn | 0+ | ||
| β+ (4%) | 210Fr | ||||||||
| 210mRa | 1800(200) keV | 2.24 µs | (8+) | ||||||
| 211Ra | 88 | 123 | 211.000898(28) | 13(2) s | α (97%) | 207Rn | 5/2(−) | ||
| β+ (3%) | 211Fr | ||||||||
| 212Ra | 88 | 124 | 211.999794(12) | 13.0(2) s | α (85%) | 208Rn | 0+ | ||
| β+ (15%) | 212Fr | ||||||||
| 212m1Ra | 1958.4(5) keV | 10.9(4) µs | (8)+ | ||||||
| 212m2Ra | 2613.4(5) keV | 0.85(13) µs | (11)− | ||||||
| 213Ra | 88 | 125 | 213.000384(22) | 2.74(6) min | α (80%) | 209Rn | 1/2− | ||
| β+ (20%) | 213Fr | ||||||||
| 213mRa | 1769(6) keV | 2.1(1) ms | IT (99%) | 213Ra | 17/2−# | ||||
| α (1%) | 209Rn | ||||||||
| 214Ra | 88 | 126 | 214.000108(10) | 2.46(3) s | α (99.94%) | 210Rn | 0+ | ||
| β+ (.06%) | 214Fr | ||||||||
| 215Ra | 88 | 127 | 215.002720(8) | 1.55(7) ms | α | 211Rn | (9/2+)# | ||
| 215m1Ra | 1877.8(5) keV | 7.1(2) µs | (25/2+) | ||||||
| 215m2Ra | 2246.9(5) keV | 1.39(7) µs | (29/2−) | ||||||
| 215m3Ra | 3756.6(6)+X keV | 0.555(10) µs | (43/2−) | ||||||
| 216Ra | 88 | 128 | 216.003533(9) | 182(10) ns | α | 212Rn | 0+ | ||
| ε (1×10−8%) | 216Fr | ||||||||
| 217Ra | 88 | 129 | 217.006320(9) | 1.63(17) µs | α | 213Rn | (9/2+) | ||
| 218Ra | 88 | 130 | 218.007140(12) | 25.2(3) µs | α | 214Rn | 0+ | ||
| 219Ra | 88 | 131 | 219.010085(9) | 10(3) ms | α | 215Rn | (7/2)+ | ||
| 220Ra | 88 | 132 | 220.011028(10) | 17.9(14) ms | α | 216Rn | 0+ | ||
| 221Ra | 88 | 133 | 221.013917(5) | 28(2) s | α | 217Rn | 5/2+ | ||
| CD (1.2×10−10%) | 207 Pb 14 C | ||||||||
| 222Ra | 88 | 134 | 222.015375(5) | 38.0(5) s | α | 218Rn | 0+ | 痕量[n 4] | |
| CD (3×10−8%) | 208 Pb 14 C | ||||||||
| 223Ra[n 5] | Actinium X | 88 | 135 | 223.0185022(27) | 11.43(5) d | α | 219Rn | 3/2+ | 痕量[n 6] |
| CD (6.4×10−8%) | 209 Pb 14 C | ||||||||
| 224Ra | Thorium X | 88 | 136 | 224.0202118(24) | 3.6319(23) d | α | 220Rn | 0+ | 痕量[n 7] |
| CD (4.3×10−9%) | 210 Pb 14 C | ||||||||
| 225Ra | 88 | 137 | 225.023612(3) | 14.9(2) d | β− | 225Ac | 1/2+ | ||
| 226Ra | Radium[n 8] | 88 | 138 | 226.0254098(25) | 1600(7) y | α | 222Rn | 0+ | 痕量[n 4] |
| CD (2.6×10−9%) | 212 Pb 14 C | ||||||||
| 227Ra | 88 | 139 | 227.0291778(25) | 42.2(5) min | β− | 227Ac | 3/2+ | ||
| 228Ra | Mesothorium 1 | 88 | 140 | 228.0310703(26) | 5.75(3) y | β− | 228Ac | 0+ | 痕量[n 7] |
| 229Ra | 88 | 141 | 229.034958(20) | 4.0(2) min | β− | 229Ac | 5/2(+) | ||
| 230Ra | 88 | 142 | 230.037056(13) | 93(2) min | β− | 230Ac | 0+ | ||
| 231Ra | 88 | 143 | 231.04122(32)# | 103(3) s | β− | 231Ac | (5/2+) | ||
| 231mRa | 66.21(9) keV | ~53 µs | (1/2+) | ||||||
| 232Ra | 88 | 144 | 232.04364(30)# | 250(50) s | β− | 232Ac | 0+ | ||
| 233Ra | 88 | 145 | 233.04806(50)# | 30(5) s | β− | 233Ac | 1/2+# | ||
| 234Ra | 88 | 146 | 234.05070(53)# | 30(10) s | β− | 234Ac | 0+ | ||
- ^ 1.0 1.1 1.2 畫上#號的數據代表沒有經過實驗的証明，僅為理論推測。
- ^ 2.0 2.1 2.2 用括號括起來的數據代表不確定性。
- ^ 穩定的衰變產物以粗體表示。
- ^ 4.0 4.1 238U的衰变产物
- ^ 用于治疗骨癌
- ^ 235U的衰变产物
- ^ 7.0 7.1 232Th的衰变产物
- ^ 这个元素的名称来源
| ← | 同位素列表 | → |
| 鈁的同位素 | 鐳的同位素 | 錒的同位素 |
参考文獻
[编辑]- ^ First observations of short-lived pear-shaped atomic nuclei. [2023-05-19]. （原始内容存档于2018-06-12）.
- ^ Universal Nuclide Chart. nucleonica. [2015-11-01]. （原始内容
存档于2017-02-19）.
- 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).
- 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.