Atomic number: 105 Symbol: Db
(this element does not have any stable isotopes)
Atomic weight of the most stable isotope: 268.12545(57) u
| Isotope | Atomic weight/u | Half-life |
| 255 | 255.10740(45) | 1.6 s +6-4 |
| 256 | 256.10813(31) | 1.6 s +5-3 |
| 257 | 257.10772(24) | 0.76 s +15-11 |
| 258 | 258.10923(37) | 4.0 s 10 |
| 259 | 259.10961(23) | 0.51 s 16 |
| 260 | 260.11130(25) | 1.52 s 13 |
| 261 | 261.11206(25) | 1.8 s 4 |
| 262 | 262.11408(20) | 35 s 5 |
| 263 | 263.11499(18) | 27 s +10-7 |
| 264 | 264.11740(25) | 3 m SY |
| 265 | 265.11860(30) | 15 m SY |
| 267 | 267.12238(50) | 73 m +350-33 |
| 268 | 268.12545(57) | 32 h +11-7 |
Units: y = year, d = day, h = hour, m = minute, s = second, ms = millisecond, µs = microsecond.
Numbers in italics are uncertainties with the same unit as the last digit of the half-life.
SY indicates that the half-life was estimated from systematic trends.
Atomic weights were obtained from NIST Database 144
Half-lifes of radioactive isotopes were extracted from the NuDat 2 database
(Atomic Line List 2.05b16, compiled on Jan 13, 2012)