Barium-135m
Properties and data of the isotope 135mBa.
See also: List of individual Barium isotopes (and general data sources).
General data
Name of the isotope:Barium-135m; Ba-135mSymbol:135mBa or 135m56BaMass number A:135 (= number of nucleons)Atomic number Z:56 (= number of protons)Neutrons N:79Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.4107142857143 (= neutron-proton ratio)Neutron excess (N-Z):23Excitation energy:268.218(20) keVIsotopic mass:134.905688(2) u (atomic weight of Barium-135m)Nuclide mass:134.8749696 u (calculated nuclear mass without electrons)Mass excess:-87.85106 MeVMass defect:1.217042156 u (per nucleus)Nuclear binding energy:1133.66746606 MeV (per nucleus)
8.39753679 MeV (average binding energy per nucleon)Half-life:28.7(2) hDecay constant λ:6.708741584978 × 10-6 s-1Specific activity α:3.014999016242 × 10+16 Bq g-1
814864.59898454 Ci g-1Spin and parity:
(nuclear angular momentum)11/2-Magnetic dipole moment:μ(μN) = -1.001(15)Quadrupole moment Q:+0.96(8) barn (100 fm2)Nuclear g-factor:gl = -0.182
Radioactive Decay
Half-life T½ = 28.7(2) h (hours) respectively 1.03320 × 105 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| Iso | 135Ba | 100 % | 0.2682 MeV | |
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 |
|---|
| 135Ba | | stable | 3/2+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 79) and isobaric (same nucleon number A = 135) with Barium-135m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 79 | Isobar A = 135 |
|---|
| 44 | 123Ru | |
| 45 | 124Rh | |
| 46 | 125Pd | |
| 47 | 126Ag | |
| 48 | 127Cd | |
| 49 | 128In | 135In |
| 50 | 129Sn | 135Sn |
| 51 | 130Sb | 135Sb |
| 52 | 131Te | 135Te |
| 53 | 132I | 135I |
| 54 | 133Xe | 135Xe |
| 55 | 134Cs | 135Cs |
| 56 | 135Ba | 135Ba |
| 57 | 136La | 135La |
| 58 | 137Ce | 135Ce |
| 59 | 138Pr | 135Pr |
| 60 | 139Nd | 135Nd |
| 61 | 140Pm | 135Pm |
| 62 | 141Sm | 135Sm |
| 63 | 142Eu | 135Eu |
| 64 | 143Gd | 135Gd |
| 65 | 144Tb | 135Tb |
| 66 | 145Dy | |
| 67 | 146Ho | |
| 68 | 147Er | |
| 69 | 148Tm | |
| 70 | 149Yb | |
| 71 | 150Lu | |
External data and identifiers
Last update: 2020-10-19
Perma link: https://www.chemlin.org/isotope/barium-135m
© 1996 - 2026 ChemLin
