Promethium-142m
Properties and data of the isotope 142mPm.
See also: list of Promethium isotopes.
General data
Name of the isotope:Promethium-142m; Pm-142mSymbol:142mPm or 142m61PmMass number A:142 (= number of nucleons)Atomic number Z:61 (= number of protons)Neutrons N:81Isotopic mass:141.912890(25) u (atomic weight of Promethium-142m)
Excitation energy: 883.17 (16) keVNuclide mass:141.8794292 u (calculated nuclear mass without electrons)Mass excess:-81.14244 MeVMass defect:1.266295148 u (per nucleus)Nuclear binding energy:1179.54633259 MeV (per nucleus)
8.30666431 MeV (average binding energy per nucleon)Half-life:2.0(2) msDecay constant λ:346.57359027997 s-1Specific activity α:1.480223389361 × 10+24 Bq g-1
40006037550316 Ci g-1Spin and parity:
(nuclear angular momentum)(8)-
Radioactive Decay
Half-life T½ = 2.0(2) ms respectively 2.0 × 10-3 seconds s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
---|
Iso | 142Pm | 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 |
---|
142Pm | | 40.5(5) s | 1+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 81) and isobaric (same nucleon number A = 142) with Promethium-142m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
Z | Isotone N = 81 | Isobar A = 142 |
45 | 126Rh | |
46 | 127Pd | |
47 | 128Ag | |
48 | 129Cd | |
49 | 130In | |
50 | 131Sn | |
51 | 132Sb | |
52 | 133Te | 142Te |
53 | 134I | 142I |
54 | 135Xe | 142Xe |
55 | 136Cs | 142Cs |
56 | 137Ba | 142Ba |
57 | 138La | 142La |
58 | 139Ce | 142Ce |
59 | 140Pr | 142Pr |
60 | 141Nd | 142Nd |
61 | 142Pm | 142Pm |
62 | 143Sm | 142Sm |
63 | 144Eu | 142Eu |
64 | 145Gd | 142Gd |
65 | 146Tb | 142Tb |
66 | 147Dy | 142Dy |
67 | 148Ho | 142Ho |
68 | 149Er | |
69 | 150Tm | |
70 | 151Yb | |
71 | 152Lu | |
72 | 153Hf | |
External data and identifiers
Last update: 2020-10-20
Perma link: https://www.chemlin.org/isotope/promethium-142m
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