Average atomic weight: 101.07(2) u
| Isotope | Fraction | Atomic weight/u |
| 96 | 0.0554(14) | 95.90759025(49) |
| 98 | 0.0187(3) | 97.9052868(69) |
| 99 | 0.1276(14) | 98.9059341(11) |
| 100 | 0.1260(7) | 99.9042143(11) |
| 101 | 0.1706(2) | 100.9055769(12) |
| 102 | 0.3155(14) | 101.9043441(12) |
| 104 | 0.1862(27) | 103.9054275(28) |
Atomic weights and isotopic compositions were obtained from NIST Database 144
The Atomic Line List does not contain any data for this element
(Atomic Line List v3.00b5)
