Iridium-169
Properties and data of the isotope 169Ir.
See also: List of individual Iridium isotopes (and general data sources).
General data
Name of the isotope:Iridium-169; Ir-169Symbol:169Ir or 16977IrMass 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):15Isotopic mass:168.976281(25) u (atomic weight of Iridium-169)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)Separation energy:SN = 11.50(6) MeV (first neutron)
SP = -0.612(22) MeV (first proton)Half-life:353(4) msDecay constant λ:1.9635897466287 s-1Specific activity α:7.038698836503 × 10+21 Bq g-1
190235103689.28 Ci g-1Spin and parity:
(nuclear angular momentum)(1/2+)Year of discovery:1978
Radioactive Decay
Half-life T½ = 353(4) ms respectively 3.53 × 10-1 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| α | 165Re | 45(12) % | 6.141(4) MeV | |
| p | 168Os | ? | | |
| EC/β+ | 169Os | ? | 8,63(3) MeV | |
Parent Nuclides
Direct parent isotope is: 173Au.
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 |
|---|
| 169mIr | 153(24) keV | 281(4) ms | (11/2-) |
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-169. 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 | |
External data and identifiers
Last update: 2020-10-21
Perma link: https://www.chemlin.org/isotope/iridium-169
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