Barium-136m
Properties and data of the isotope 136mBa.
See also: List of individual Barium isotopes (and general data sources).
General data
Name of the isotope:Barium-136m; Ba-136mSymbol:136mBa or 136m56BaMass number A:136 (= number of nucleons)Atomic number Z:56 (= number of protons)Neutrons N:80Excitation energy:2030.535(18) keVIsotopic mass:135.904576(2) u (atomic weight of Barium-136m)Nuclide mass:135.8738576 u (calculated nuclear mass without electrons)Mass excess:-88.88688 MeVMass defect:1.226819072 u (per nucleus)Nuclear binding energy:1142.77460465 MeV (per nucleus)
8.40275445 MeV (average binding energy per nucleon)Half-life:308.4(19) msDecay constant λ:2.247558951232 s-1Specific activity α:1.002601229283 × 10+22 Bq g-1
270973305211.84 Ci g-1Spin and parity:
(nuclear angular momentum)7-
Radioactive Decay
Half-life T½ = 308.4(19) ms respectively 3.084 × 10-1 seconds s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
|---|
| Iso | 136Ba | 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 |
|---|
| 136Ba | | stable | 0+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 80) and isobaric (same nucleon number A = 136) with Barium-136m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 80 | Isobar A = 136 |
| 44 | 124Ru | |
| 45 | 125Rh | |
| 46 | 126Pd | |
| 47 | 127Ag | |
| 48 | 128Cd | |
| 49 | 129In | 136In |
| 50 | 130Sn | 136Sn |
| 51 | 131Sb | 136Sb |
| 52 | 132Te | 136Te |
| 53 | 133I | 136I |
| 54 | 134Xe | 136Xe |
| 55 | 135Cs | 136Cs |
| 56 | 136Ba | 136Ba |
| 57 | 137La | 136La |
| 58 | 138Ce | 136Ce |
| 59 | 139Pr | 136Pr |
| 60 | 140Nd | 136Nd |
| 61 | 141Pm | 136Pm |
| 62 | 142Sm | 136Sm |
| 63 | 143Eu | 136Eu |
| 64 | 144Gd | 136Gd |
| 65 | 145Tb | 136Tb |
| 66 | 146Dy | |
| 67 | 147Ho | |
| 68 | 148Er | |
| 69 | 149Tm | |
| 70 | 150Yb | |
| 71 | 151Lu | |
External data and identifiers
Last update: 2020-10-19
Perma link: https://www.chemlin.org/isotope/barium-136m
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