Mercury-203m
Properties and data of the isotope 203mHg.
See also: List of individual Mercury isotopes (and general data sources).
General data
Name of the isotope:Mercury-203m; Hg-203mSymbol:203mHg or 203m80HgMass number A:203 (= number of nucleons)Atomic number Z:80 (= number of protons)Neutrons N:123Isotopic mass:202.9728723(17) u (atomic weight of Mercury-203m)
Excitation energy: 933.14(23) keVNuclide mass:202.9289907 u (calculated nuclear mass without electrons)Mass excess:-25.26929 MeVMass defect:1.718914928 u (per nucleus)Nuclear binding energy:1601.15894194 MeV (per nucleus)
7.88748247 MeV (average binding energy per nucleon)Half-life:24(4) μsDecay constant λ:28881.132523331 s-1Specific activity α:8.610210309405 × 10+25 Bq g-1
2.32708386740 × 10+15 Ci g-1Spin and parity:
(nuclear angular momentum)
Radioactive Decay
Half-life T½ = 24(4) μs respectively 2.4 × 10-5 seconds s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
|---|
| Iso | 203Hg | 100 % | | |
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 |
|---|
| 203Hg | | 46.594(12) d | 5/2- |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 123) and isobaric (same nucleon number A = 203) with Mercury-203m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 123 | Isobar A = 203 |
| 74 | 197W | |
| 75 | 198Re | |
| 76 | 199Os | 203Os |
| 77 | 200Ir | 203Ir |
| 78 | 201Pt | 203Pt |
| 79 | 202Au | 203Au |
| 80 | 203Hg | 203Hg |
| 81 | 204Tl | 203Tl |
| 82 | 205Pb | 203Pb |
| 83 | 206Bi | 203Bi |
| 84 | 207Po | 203Po |
| 85 | 208At | 203At |
| 86 | 209Rn | 203Rn |
| 87 | 210Fr | 203Fr |
| 88 | 211Ra | 203Ra |
| 89 | 212Ac | 203Ac |
| 90 | 213Th | |
| 91 | 214Pa | |
| 92 | 215U | |
Last update: 2020-10-22
Perma link: https://www.chemlin.org/isotope/mercury-203m
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