Iridium-173m
Properties and data of the isotope 173mIr.
See also: List of individual Iridium isotopes (and general data sources).
General data
Name of the isotope:Iridium-173m; Ir-173mSymbol:173mIr or 173m77IrMass number A:173 (= number of nucleons)Atomic number Z:77 (= number of protons)Neutrons N:96Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.2467532467532 (= neutron-proton ratio)Neutron excess (N-Z):19Excitation energy:226(18) keVIsotopic mass:172.967505(12) u (atomic weight of Iridium-173m)Nuclide mass:172.9252688 u (calculated nuclear mass without electrons)Mass excess:-30.2689 MeVMass defect:1.4668544 u (per nucleus)Nuclear binding energy:1366.36607247 MeV (per nucleus)
7.89806978 MeV (average binding energy per nucleon)Half-life:2.20(5) sDecay constant λ:0.31506690025452 s-1Specific activity α:1.103126310253 × 10+21 Bq g-1
29814224601.451 Ci g-1Spin and parity:
(nuclear angular momentum)(11/2-)
Radioactive Decay
Half-life T½ = 2.20(5) s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| α | 169Re | 12(1) % | | |
| EC/β+ | 173Os | 88(1) % | | |
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 |
|---|
| 173Ir | | 9.0(8) s | (3/2+,5/2+) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 96) and isobaric (same nucleon number A = 173) with Iridium-173m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 96 | Isobar A = 173 |
|---|
| 55 | 151Cs | |
| 56 | 152Ba | |
| 57 | 153La | |
| 58 | 154Ce | |
| 59 | 155Pr | |
| 60 | 156Nd | |
| 61 | 157Pm | |
| 62 | 158Sm | |
| 63 | 159Eu | |
| 64 | 160Gd | |
| 65 | 161Tb | |
| 66 | 162Dy | 173Dy |
| 67 | 163Ho | 173Ho |
| 68 | 164Er | 173Er |
| 69 | 165Tm | 173Tm |
| 70 | 166Yb | 173Yb |
| 71 | 167Lu | 173Lu |
| 72 | 168Hf | 173Hf |
| 73 | 169Ta | 173Ta |
| 74 | 170W | 173W |
| 75 | 171Re | 173Re |
| 76 | 172Os | 173Os |
| 77 | 173Ir | 173Ir |
| 78 | 174Pt | 173Pt |
| 79 | 175Au | 173Au |
| 80 | 176Hg | 173Hg |
| 81 | 177Tl | |
| 82 | 178Pb | |
Last update: 2020-10-21
Perma link: https://www.chemlin.org/isotope/iridium-173m
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