Xenon-131m
Properties and data of the isotope 131mXe.
See also: List of individual Xenon isotopes (and general data sources).
General data
Name of the isotope:Xenon-131m; Xe-131mSymbol:131mXe or 131m54XeMass number A:131 (= number of nucleons)Atomic number Z:54 (= number of protons)Neutrons N:77Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.4259259259259 (= neutron-proton ratio)Neutron excess (N-Z):23Excitation energy:163.930(8) keVIsotopic mass:130.905084(2) u (atomic weight of Xenon-131m)Nuclide mass:130.8754626 u (calculated nuclear mass without electrons)Mass excess:-88.41368 MeVMass defect:1.18466626 u (per nucleus)Nuclear binding energy:1103.50951319 MeV (per nucleus)
8.42373674 MeV (average binding energy per nucleon)Half-life:11.84(4) dDecay constant λ:6.775791226382 × 10-7 s-1Specific activity α:3.138828400215 × 10+15 Bq g-1
84833.200005814 Ci g-1Spin and parity:
(nuclear angular momentum)11/2-Magnetic dipole moment:μ(μN) = -0.993989(12)Quadrupole moment Q:+0.73(3) barn (100 fm2)Nuclear g-factor:gl = -0.18072527272727
Radioactive Decay
Half-life T½ = 11.84(4) d respectively 1.022976 × 106 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| Iso | 131Xe | 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 |
|---|
| 131Xe | | stable | 3/2+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 77) and isobaric (same nucleon number A = 131) with Xenon-131m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 77 | Isobar A = 131 |
|---|
| 43 | 120Tc | |
| 44 | 121Ru | |
| 45 | 122Rh | |
| 46 | 123Pd | |
| 47 | 124Ag | 131Ag |
| 48 | 125Cd | 131Cd |
| 49 | 126In | 131In |
| 50 | 127Sn | 131Sn |
| 51 | 128Sb | 131Sb |
| 52 | 129Te | 131Te |
| 53 | 130I | 131I |
| 54 | 131Xe | 131Xe |
| 55 | 132Cs | 131Cs |
| 56 | 133Ba | 131Ba |
| 57 | 134La | 131La |
| 58 | 135Ce | 131Ce |
| 59 | 136Pr | 131Pr |
| 60 | 137Nd | 131Nd |
| 61 | 138Pm | 131Pm |
| 62 | 139Sm | 131Sm |
| 63 | 140Eu | 131Eu |
| 64 | 141Gd | |
| 65 | 142Tb | |
| 66 | 143Dy | |
| 67 | 144Ho | |
| 68 | 145Er | |
| 69 | 146Tm | |
External data and identifiers
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/xenon-131m
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