Neodymium-139m2
Properties and data of the isotope 139m2Nd.
See also: List of individual Neodymium isotopes (and general data sources).
General data
Name of the isotope:Neodymium-139m2; Nd-139m2Symbol:139m2Nd or 139m260NdMass number A:139 (= number of nucleons)Atomic number Z:60 (= number of protons)Neutrons N:79Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.3166666666667 (= neutron-proton ratio)Neutron excess (N-Z):19Excitation energy:2616.9(6) keVIsotopic mass:138.91195(3) u (atomic weight of Neodymium-139m2)Nuclide mass:138.8790377 u (calculated nuclear mass without electrons)Mass excess:-82.01805 MeVMass defect:1.242080284 u (per nucleus)Nuclear binding energy:1156.99033206 MeV (per nucleus)
8.32367145 MeV (average binding energy per nucleon)Half-life:277(2) nsDecay constant λ:2502336.3919132 s-1Specific activity α:1.091987118191 × 10+28 Bq g-1
2.951316535653 × 10+17 Ci g-1Spin and parity:
(nuclear angular momentum)(23/2+)
Radioactive Decay
Half-life T½ = 277(2) ns respectively 2.77 × 10-7 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| Iso | 139Nd | 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 |
|---|
| 139Nd | | 29.7(5) min | 3/2+ |
| 139m1Nd | 231.16(5) keV | 5.50(20) h | 11/2- |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 79) and isobaric (same nucleon number A = 139) with Neodymium-139m2. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 79 | Isobar A = 139 |
|---|
| 44 | 123Ru | |
| 45 | 124Rh | |
| 46 | 125Pd | |
| 47 | 126Ag | |
| 48 | 127Cd | |
| 49 | 128In | |
| 50 | 129Sn | 139Sn |
| 51 | 130Sb | 139Sb |
| 52 | 131Te | 139Te |
| 53 | 132I | 139I |
| 54 | 133Xe | 139Xe |
| 55 | 134Cs | 139Cs |
| 56 | 135Ba | 139Ba |
| 57 | 136La | 139La |
| 58 | 137Ce | 139Ce |
| 59 | 138Pr | 139Pr |
| 60 | 139Nd | 139Nd |
| 61 | 140Pm | 139Pm |
| 62 | 141Sm | 139Sm |
| 63 | 142Eu | 139Eu |
| 64 | 143Gd | 139Gd |
| 65 | 144Tb | 139Tb |
| 66 | 145Dy | 139Dy |
| 67 | 146Ho | |
| 68 | 147Er | |
| 69 | 148Tm | |
| 70 | 149Yb | |
| 71 | 150Lu | |
Last update: 2020-10-20
Perma link: https://www.chemlin.org/isotope/neodymium-139m2
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