Promethium-142
Properties and data of the isotope 142Pm.
See also: List of individual Promethium isotopes (and general data sources).
General data
Name of the isotope:Promethium-142; Pm-142Symbol:142Pm or 14261PmMass number A:142 (= number of nucleons)Atomic number Z:61 (= number of protons)Neutrons N:81Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.327868852459 (= neutron-proton ratio)Neutron excess (N-Z):20Isotopic mass:141.912890(25) u (atomic weight of Promethium-142)Nuclide 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)Separation energy:SN = 8.690(27) MeV (first neutron)
SP = 4.238(24) MeV (first proton)Half-life:40.5(5) sDecay constant λ:0.017114745199011 s-1Specific activity α:7.309745132650 × 10+19 Bq g-1
1975606792.6082 Ci g-1Spin and parity:
(nuclear angular momentum)1+Year of discovery:1959
Radioactive Decay
Half-life T½ = 40.5(5) s respectively 4.05 × 101 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| EC/β+ | 142Nd | 100 % | 4.808(24) MeV | |
Parent Nuclides
Direct parent isotope is: 142Sm.
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 |
|---|
| 142mPm | 883.17 (16) keV | 2.0(2) ms | (8)- |
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-142. 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-142
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