Neodymium-138m
Properties and data of the isotope 138mNd.
See also: List of individual Neodymium isotopes (and general data sources).
General data
Name of the isotope:Neodymium-138m; Nd-138mSymbol:138mNd or 138m60NdMass number A:138 (= number of nucleons)Atomic number Z:60 (= number of protons)Neutrons N:78Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3 (= neutron-proton ratio)Neutron excess (N-Z):18Excitation energy:3174.5(4) keVIsotopic mass:137.911950(12) u (atomic weight of Neodymium-138m)Nuclide mass:137.8790377 u (calculated nuclear mass without electrons)Mass excess:-82.01805 MeVMass defect:1.233415368 u (per nucleus)Nuclear binding energy:1148.9190148 MeV (per nucleus)
8.32550011 MeV (average binding energy per nucleon)Half-life:370(5) nsDecay constant λ:1873370.7582701 s-1Specific activity α:8.234819408167 × 10+27 Bq g-1
2.225626867072 × 10+17 Ci g-1Spin and parity:
(nuclear angular momentum)10+Magnetic dipole moment:μ(μN) = -1.74(4)Nuclear g-factor:gl = -0.174
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 |
|---|
| 138Nd | | 5.04(9) h | 0+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 78) and isobaric (same nucleon number A = 138) with Neodymium-138m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 78 | Isobar A = 138 |
| 43 | 121Tc | |
| 44 | 122Ru | |
| 45 | 123Rh | |
| 46 | 124Pd | |
| 47 | 125Ag | |
| 48 | 126Cd | |
| 49 | 127In | |
| 50 | 128Sn | 138Sn |
| 51 | 129Sb | 138Sb |
| 52 | 130Te | 138Te |
| 53 | 131I | 138I |
| 54 | 132Xe | 138Xe |
| 55 | 133Cs | 138Cs |
| 56 | 134Ba | 138Ba |
| 57 | 135La | 138La |
| 58 | 136Ce | 138Ce |
| 59 | 137Pr | 138Pr |
| 60 | 138Nd | 138Nd |
| 61 | 139Pm | 138Pm |
| 62 | 140Sm | 138Sm |
| 63 | 141Eu | 138Eu |
| 64 | 142Gd | 138Gd |
| 65 | 143Tb | 138Tb |
| 66 | 144Dy | 138Dy |
| 67 | 145Ho | |
| 68 | 146Er | |
| 69 | 147Tm | |
| 70 | 148Yb | |
| 71 | 149Lu | |
External data and identifiers
Last update: 2020-10-20
Perma link: https://www.chemlin.org/isotope/neodymium-138m
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