Tellurium-123m
Properties and data of the isotope 123mTe.
See also: List of individual Tellurium isotopes (and general data sources).
General data
Name of the isotope:Tellurium-123m; Te-123mSymbol:123mTe or 123m52TeMass number A:123 (= number of nucleons)Atomic number Z:52 (= number of protons)Neutrons N:71Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.3653846153846 (= neutron-proton ratio)Neutron excess (N-Z):19Excitation energy:247.47(4) keVIsotopic mass:122.90427(1) u (atomic weight of Tellurium-123m)Nuclide mass:122.8757456 u (calculated nuclear mass without electrons)Mass excess:-89.17192 MeVMass defect:1.1178407 u (per nucleus)Nuclear binding energy:1041.26190501 MeV (per nucleus)
8.46554394 MeV (average binding energy per nucleon)Half-life:119.2(1) dDecay constant λ:6.730316117480 × 10-8 s-1Specific activity α:3.322205876341 × 10+14 Bq g-1
8978.9348009235 Ci g-1Spin and parity:
(nuclear angular momentum)11/2-Magnetic dipole moment:μ(μN) = - 0.927(8)Nuclear g-factor:gl = -0.16854545454545
Radioactive Decay
Half-life T½ = 119.2(1) d respectively 1.0298880 × 107 seconds s.
Decay
mode | Daughter | Probability | Decay energy | γ energy
(intensity) |
|---|
| Iso | 123Te | 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 |
|---|
| 123Te | | 9.2 × 1016 a | 1/2+ |
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 71) and isobaric (same nucleon number A = 123) with Tellurium-123m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
| Z | Isotone N = 71 | Isobar A = 123 |
|---|
| 40 | 111Zr | |
| 41 | 112Nb | |
| 42 | 113Mo | |
| 43 | 114Tc | |
| 44 | 115Ru | 123Ru |
| 45 | 116Rh | 123Rh |
| 46 | 117Pd | 123Pd |
| 47 | 118Ag | 123Ag |
| 48 | 119Cd | 123Cd |
| 49 | 120In | 123In |
| 50 | 121Sn | 123Sn |
| 51 | 122Sb | 123Sb |
| 52 | 123Te | 123Te |
| 53 | 124I | 123I |
| 54 | 125Xe | 123Xe |
| 55 | 126Cs | 123Cs |
| 56 | 127Ba | 123Ba |
| 57 | 128La | 123La |
| 58 | 129Ce | 123Ce |
| 59 | 130Pr | 123Pr |
| 60 | 131Nd | |
| 61 | 132Pm | |
| 62 | 133Sm | |
| 63 | 134Eu | |
| 64 | 135Gd | |
| 65 | 136Tb | |
Last update: 2020-10-18
Perma link: https://www.chemlin.org/isotope/tellurium-123m
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