Most of the isotope data on this site has been obtained from the National Nuclear Data Center.
Naturally Occurring Isotopes
| Mass Number | Natural Abundance | Half-life |
| 124 | 0.0952% | >= 1.6×10+14 years |
| 126 | 0.0890% | STABLE |
| 128 | 1.9102% | STABLE |
| 129 | 26.4006% | STABLE |
| 130 | 4.0710% | STABLE |
| 131 | 21.232% | STABLE |
| 132 | 26.9086% | STABLE |
| 134 | 10.4357% | > 5.8×10+22 years |
| 136 | 8.8573% | > 2.4×10+21 years |
Known Isotopes
| Mass Number | Half-life | Decay Mode | Branching Percentage |
| 108 | No Data Available | No Data Available | No Data Available |
| 109 | 13 milliseconds | Alpha Decay | 100.00% |
| 110 | 93 milliseconds | Electron Capture | No Data Available |
| Electron Capture with delayed Proton Emission | No Data Available | ||
| Alpha Decay | 64.00% | ||
| 111 | 0.81 seconds | Electron Capture | 90.00% |
| Alpha Decay | 10.00% | ||
| 112 | 2.7 seconds | Electron Capture | 99.16% |
| Alpha Decay | 0.84% | ||
| 113 | 2.74 seconds | Electron Capture | No Data Available |
| Electron Capture with delayed Proton Emission | 7.00% | ||
| Alpha Decay | ~ 0.01% | ||
| Electron Capture with delayed Alpha Decay | ~ 7.0×10-3 % | ||
| 114 | 10.0 seconds | Electron Capture | 100.00% |
| 115 | 18 seconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | 0.34% | ||
| Alpha Decay | 3.0×10-4 % | ||
| 116 | 59 seconds | Electron Capture | 100.00% |
| 117 | 61 seconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | 2.9×10-3 % | ||
| 118 | 3.8 minutes | Electron Capture | 100.00% |
| 119 | 5.8 minutes | Electron Capture | 100.00% |
| 120 | 40 minutes | Electron Capture | 100.00% |
| 121 | 40.1 minutes | Electron Capture | 100.00% |
| 122 | 20.1 hours | Electron Capture | 100.00% |
| 123 | 2.08 hours | Electron Capture | 100.00% |
| 124 | >= 1.6×10+14 years | Double Electron Capture | No Data Available |
| 125 | 16.9 hours | Electron Capture | 100.00% |
| 125m | 57 seconds | Isomeric Transition | 100.00% |
| 126 | STABLE | - | - |
| 127 | 36.346 days | Electron Capture | 100.00% |
| 127m | 69.2 seconds | Isomeric Transition | 100.00% |
| 128 | STABLE | - | - |
| 129 | STABLE | - | - |
| 129m | 8.88 days | Isomeric Transition | 100.00% |
| 130 | STABLE | - | - |
| 131 | STABLE | - | - |
| 131m | 11.84 days | Isomeric Transition | 100.00% |
| 132 | STABLE | - | - |
| 132m | 8.39 milliseconds | Isomeric Transition | 100.00% |
| 133 | 5.2475 days | Beta-minus Decay | 100.00% |
| 133m | 2.198 days | Isomeric Transition | 100.00% |
| 134 | > 5.8×10+22 years | Double Beta-minus Decay | No Data Available |
| 134m | 290 milliseconds | Isomeric Transition | 100.00% |
| 135 | 9.14 hours | Beta-minus Decay | 100.00% |
| 135m | 15.29 minutes | Isomeric Transition | > 99.40% |
| Beta-minus Decay | < 0.60% | ||
| 136 | > 2.4×10+21 years | Double Beta-minus Decay | No Data Available |
| 137 | 3.818 minutes | Beta-minus Decay | 100.00% |
| 138 | 14.08 minutes | Beta-minus Decay | 100.00% |
| 139 | 39.68 seconds | Beta-minus Decay | 100.00% |
| 140 | 13.60 seconds | Beta-minus Decay | 100.00% |
| 141 | 1.73 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 0.04% | ||
| 142 | 1.23 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 0.21% | ||
| 143 | 0.511 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 1.00% | ||
| 144 | 0.388 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 3.00% | ||
| 145 | 188 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 5.00% | ||
| 146 | 146 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 6.90% | ||
| 147 | 0.10 seconds | Beta-minus Decay | No Data Available |
| Beta-minus Decay with delayed Neutron Emission | < 8.00% | ||
| 148 | > 408 nanoseconds | Beta-minus Decay with delayed Neutron Emission | No Data Available |
| Beta-minus Decay | No Data Available |
This page is maintained by Steve Gagnon.