Xenon-133m
Properties and data of the isotope 133mXe.
See also: List of individual Xenon isotopes (and general data sources).
General data
Name of the isotope:Xenon-133m; Xe-133mSymbol:133mXe or 133m54XeMass number A:133 (= number of nucleons)Atomic number Z:54 (= number of protons)Neutrons N:79Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.462962962963 (= neutron-proton ratio)Neutron excess (N-Z):25Excitation energy:233.221(15) keVIsotopic mass:132.9059107(26) u (atomic weight of Xenon-133m)Nuclide mass:132.8762893 u (calculated nuclear mass without electrons)Mass excess:-87.64362 MeVMass defect:1.201169392 u (per nucleus)Nuclear binding energy:1118.88208163 MeV (per nucleus)
8.41264723 MeV (average binding energy per nucleon)Half-life:2.198(13) dDecay constant λ:3.649925756158 × 10-6 s-1Specific activity α:1.665179320598 × 10+16 Bq g-1
450048.46502657 Ci g-1Spin and parity:
(nuclear angular momentum)11/2-Magnetic dipole moment:μ(μN) = -1.08241(15)Quadrupole moment Q:+0.77(3) barn (100 fm2)Nuclear g-factor:gl = -0.19680181818182
Radioactive Decay
Half-life T½ = 2.198(13) d respectively 1.899072 × 105 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| Iso | 133Xe | 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 |
|---|
| 133Xe | | 5.2475(5) d | 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 = 133) with Xenon-133m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 79 | Isobar A = 133 |
|---|
| 44 | 123Ru | |
| 45 | 124Rh | |
| 46 | 125Pd | |
| 47 | 126Ag | |
| 48 | 127Cd | 133Cd |
| 49 | 128In | 133In |
| 50 | 129Sn | 133Sn |
| 51 | 130Sb | 133Sb |
| 52 | 131Te | 133Te |
| 53 | 132I | 133I |
| 54 | 133Xe | 133Xe |
| 55 | 134Cs | 133Cs |
| 56 | 135Ba | 133Ba |
| 57 | 136La | 133La |
| 58 | 137Ce | 133Ce |
| 59 | 138Pr | 133Pr |
| 60 | 139Nd | 133Nd |
| 61 | 140Pm | 133Pm |
| 62 | 141Sm | 133Sm |
| 63 | 142Eu | 133Eu |
| 64 | 143Gd | |
| 65 | 144Tb | |
| 66 | 145Dy | |
| 67 | 146Ho | |
| 68 | 147Er | |
| 69 | 148Tm | |
| 70 | 149Yb | |
| 71 | 150Lu | |
External data and identifiers
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/xenon-133m
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