| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
鋦有从233Cm到251Cm共19种同位素以及10种同核异构体,全部都有放射性。其中,247Cm最稳定,半衰期1560万年,是之后所有原子序更高的核素半衰期的至少一万倍。它是R-过程产生的绝种核素(英语:extinct radionuclide)。[1][2]锔最稳定的同核异构体则是246mCm,半衰期1.12秒。
| 符號 | Z | N | 同位素質量(u) [n 1][n 2] | 半衰期 [n 1][n 2] | 衰變 方式[3] | 衰變 產物 [n 3] | 原子核 自旋[n 1] |
|---|---|---|---|---|---|---|---|
| 激發能量[n 2] | |||||||
| 233Cm | 96 | 137 | 233.05077(8) | 1# min | β+ | 233Am | 3/2+# |
| α | 229Pu | ||||||
| 234Cm | 96 | 138 | 234.05016(2) | 51(12) s | β+ | 234Am | 0+ |
| α | 230Pu | ||||||
| 235Cm | 96 | 139 | 235.05143(22)# | 5# min | β+ | 235Am | 5/2+# |
| α | 231Pu | ||||||
| 236Cm | 96 | 140 | 236.05141(22)# | 10# min | β+ | 236Am | 0+ |
| α | 232Pu | ||||||
| 237Cm | 96 | 141 | 237.05290(22)# | 20# min | β+ | 237Am | 5/2+# |
| α | 233Pu | ||||||
| 238Cm | 96 | 142 | 238.05303(4) | 2.4(1) h | ε (90%) | 238Am | 0+ |
| α (10%) | 234Pu | ||||||
| 239Cm | 96 | 143 | 239.05496(11)# | ~2.9 h | β+ (99.9%) | 239Am | (7/2−) |
| α (.1%) | 235Pu | ||||||
| 240Cm | 96 | 144 | 240.0555295(25) | 27(1) d | α (99.5%) | 236Pu | 0+ |
| ε (.5%) | 240Am | ||||||
| SF (3.9×10−6%) | (various) | ||||||
| 241Cm | 96 | 145 | 241.0576530(23) | 32.8(2) d | ε (99%) | 241Am | 1/2+ |
| α (1%) | 237Pu | ||||||
| 242Cm[n 4] | 96 | 146 | 242.0588358(20) | 162.8(2) d | α | 238Pu | 0+ |
| SF (6.33×10−6%) | (various) | ||||||
| CD (10−14%)[n 5] | 208Pb 34Si | ||||||
| 243Cm | 96 | 147 | 243.0613891(22) | 29.1(1) y | α (99.71%) | 239Pu | 5/2+ |
| ε (.29%) | 243Am | ||||||
| SF (5.3×10−9%) | (various) | ||||||
| 243mCm | 87.4(1) keV | 1.08(3) µs | 1/2+ | ||||
| 244Cm[n 4] | 96 | 148 | 244.0627526(20) | 18.10(2) y | α | 240Pu | 0+ |
| SF (1.34×10−4%) | (various) | ||||||
| 244mCm | 1040.188(12) keV | 34(2) ms | IT | 244Cm | 6+ | ||
| 245Cm | 96 | 149 | 245.0654912(22) | 8.5(1)×103 y | α | 241Pu | 7/2+ |
| SF (6.1×10−7%) | (various) | ||||||
| 245mCm | 355.90(10) keV | 290(20) ns | 1/2+ | ||||
| 246Cm | 96 | 150 | 246.0672237(22) | 4.76(4)×103 y | α (99.97%) | 242Pu | 0+ |
| SF (.0261%) | (various) | ||||||
| 246mCm | 1179.66(13) keV | 1.12(0.24) s | IT | 246Cm | 8- | ||
| 247Cm | 96 | 151 | 247.070354(5) | 1.56(5)×107 y | α | 243Pu | 9/2− |
| 248Cm | 96 | 152 | 248.072349(5) | 3.48(6)×105 y | α (91.74%) | 244Pu | 0+ |
| SF (8.26%) | (various) | ||||||
| 249Cm | 96 | 153 | 249.075953(5) | 64.15(3) min | β− | 249Bk | 1/2(+) |
| 249mCm | 48.758(17) keV | 23 µs | (7/2+) | ||||
| 250Cm | 96 | 154 | 250.078357(12) | 8,300# y | SF (80%)[n 6] | (various) | 0+ |
| α (11%) | 246Pu | ||||||
| β− (9%) | 250Bk | ||||||
| 251Cm | 96 | 155 | 251.082285(24) | 16.8(2) min | β− | 251Bk | (1/2+) |
| ← | 同位素列表 | → |
| 鋂的同位素 | 鋦的同位素 | 锫的同位素 |