Iridium-169m
Properties and data of the isotope 169mIr.
See also: List of individual Iridium isotopes (and general data sources).
General data
Name of the isotope:Iridium-169m; Ir-169mSymbol:169mIr or 169m77IrMass number A:169 (= number of nucleons)Atomic number Z:77 (= number of protons)Neutrons N:92Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.1948051948052 (= neutron-proton ratio)Neutron excess (N-Z):15Excitation energy:153(24) keVIsotopic mass:168.976281(25) u (atomic weight of Iridium-169m)Nuclide mass:168.9340448 u (calculated nuclear mass without electrons)Mass excess:-22.09411 MeVMass defect:1.423418736 u (per nucleus)Nuclear binding energy:1325.90601207 MeV (per nucleus)
7.8455977 MeV (average binding energy per nucleon)Half-life:281(4) msDecay constant λ:2.4667159450532 s-1Specific activity α:8.84220885866 × 10+21 Bq g-1
238978617801.84 Ci g-1Spin and parity:
(nuclear angular momentum)(11/2-)
Radioactive Decay
Half-life T½ = 281(4) ms respectively 2.81 × 10-1 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| α | 165Re | 72(7) % | | |
| p | 168Os | ? | | |
| EC/β+ | 169Os | ? | | |
Nuclear Isomers
Nuclear isomers or excited states with the activation energy in keV related to the ground state.
| Nuclear Isomer | Excitation Energy | Half-life | Spin |
|---|
| 169Ir | | 353(4) ms | (1/2+) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 92) and isobaric (same nucleon number A = 169) with Iridium-169m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 92 | Isobar A = 169 |
|---|
| 53 | 145I | |
| 54 | 146Xe | |
| 55 | 147Cs | |
| 56 | 148Ba | |
| 57 | 149La | |
| 58 | 150Ce | |
| 59 | 151Pr | |
| 60 | 152Nd | |
| 61 | 153Pm | |
| 62 | 154Sm | |
| 63 | 155Eu | |
| 64 | 156Gd | 169Gd |
| 65 | 157Tb | 169Tb |
| 66 | 158Dy | 169Dy |
| 67 | 159Ho | 169Ho |
| 68 | 160Er | 169Er |
| 69 | 161Tm | 169Tm |
| 70 | 162Yb | 169Yb |
| 71 | 163Lu | 169Lu |
| 72 | 164Hf | 169Hf |
| 73 | 165Ta | 169Ta |
| 74 | 166W | 169W |
| 75 | 167Re | 169Re |
| 76 | 168Os | 169Os |
| 77 | 169Ir | 169Ir |
| 78 | 170Pt | 169Pt |
| 79 | 171Au | |
| 80 | 172Hg | |
Last update: 2020-10-21
Perma link: https://www.chemlin.org/isotope/iridium-169m
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