Iridium-185
Properties and data of the isotope 185Ir.
See also: List of individual Iridium isotopes (and general data sources).
General data
Name of the isotope:Iridium-185; Ir-185Symbol:185Ir or 18577IrMass number A:185 (= number of nucleons)Atomic number Z:77 (= number of protons)Neutrons N:108Isotopic mass:184.95670(3) u (atomic weight of Iridium-185)Nuclide mass:184.9144638 u (calculated nuclear mass without electrons)Mass excess:-40.33369 MeVMass defect:1.581638392 u (per nucleus)Nuclear binding energy:1473.28667232 MeV (per nucleus)
7.96371174 MeV (average binding energy per nucleon)Separation energy:SN = 8.80(4) MeV (first neutron)
SP = 3.372(28) MeV (first proton)Half-life:14.4(1) hDecay constant λ:1.337089468672 × 10-5 s-1Specific activity α:4.376163653633 × 10+16 Bq g-1
1182746.9334144 Ci g-1Spin and parity:
(nuclear angular momentum)5/2-Magnetic dipole moment:μ(μN) = + 2.605(13)Quadrupole moment Q:- 2.06(14) barn (100 fm2)Nuclear g-factor:gl = 1.042Charge radius:5.3854(1061) femtometer fmYear of discovery:1958
Radioactive Decay
Half-life T½ = 14.4(1) h (hours) respectively 5.1840 × 104 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 185Os | 100 % | 2.470(28) MeV | |
Parent Nuclides
Direct parent isotope is: 185Pt.
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 108) and isobaric (same nucleon number A = 185) with Iridium-185. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 108 | Isobar A = 185 |
|---|
| 66 | 174Dy | |
| 67 | 175Ho | |
| 68 | 176Er | |
| 69 | 177Tm | |
| 70 | 178Yb | 185Yb |
| 71 | 179Lu | 185Lu |
| 72 | 180Hf | 185Hf |
| 73 | 181Ta | 185Ta |
| 74 | 182W | 185W |
| 75 | 183Re | 185Re |
| 76 | 184Os | 185Os |
| 77 | 185Ir | 185Ir |
| 78 | 186Pt | 185Pt |
| 79 | 187Au | 185Au |
| 80 | 188Hg | 185Hg |
| 81 | 189Tl | 185Tl |
| 82 | 190Pb | 185Pb |
| 83 | 191Bi | 185Bi |
| 84 | 192Po | |
| 85 | 193At | |
| 86 | 194Rn | |
External data and identifiers
Last update: 2020-10-21
Perma link: https://www.chemlin.org/isotope/iridium-185
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