Promethium-133m
Properties and data of the isotope 133mPm.
See also: list of Promethium isotopes.
General data
Name of the isotope:Promethium-133m; Pm-133mSymbol:133mPm or 133m61PmMass number A:133 (= number of nucleons)Atomic number Z:61 (= number of protons)Neutrons N:72Isotopic mass:132.92978(5) u (atomic weight of Promethium-133m)
Excitation energy: 129.7(7) keVNuclide mass:132.8963192 u (calculated nuclear mass without electrons)Mass excess:-65.40951 MeVMass defect:1.171420904 u (per nucleus)Nuclear binding energy:1091.17154355 MeV (per nucleus)
8.20429732 MeV (average binding energy per nucleon)Half-life:8.8 sDecay constant λ:0.07876672506363 s-1Specific activity α:3.593517525826 × 10+20 Bq g-1
9712209529.2605 Ci g-1Spin and parity:
(nuclear angular momentum)(11/2-)
Radioactive Decay
Half-life T½ = 8.8 s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
|---|
| EC/β+ | 133Nd | ? | | |
| Iso | 133Pm | ? | | |
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 |
|---|
| 133Pm | | 13.5(21) s | (3/2+) |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 72) and isobaric (same nucleon number A = 133) with Promethium-133m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 72 | Isobar A = 133 |
| 40 | 112Zr | |
| 41 | 113Nb | |
| 42 | 114Mo | |
| 43 | 115Tc | |
| 44 | 116Ru | |
| 45 | 117Rh | |
| 46 | 118Pd | |
| 47 | 119Ag | |
| 48 | 120Cd | 133Cd |
| 49 | 121In | 133In |
| 50 | 122Sn | 133Sn |
| 51 | 123Sb | 133Sb |
| 52 | 124Te | 133Te |
| 53 | 125I | 133I |
| 54 | 126Xe | 133Xe |
| 55 | 127Cs | 133Cs |
| 56 | 128Ba | 133Ba |
| 57 | 129La | 133La |
| 58 | 130Ce | 133Ce |
| 59 | 131Pr | 133Pr |
| 60 | 132Nd | 133Nd |
| 61 | 133Pm | 133Pm |
| 62 | 134Sm | 133Sm |
| 63 | 135Eu | 133Eu |
| 64 | 136Gd | |
| 65 | 137Tb | |
| 66 | 138Dy | |
External data and identifiers
Last update: 2020-10-20
Perma link: https://www.chemlin.org/isotope/promethium-133m
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