See also: List of individual Antimony isotopes (and general data sources).
General data
Name of the isotope:Antimony-126m1; Sb-126m1Symbol:126m1Sb or 126m151SbMass number A:126 (= number of nucleons)Atomic number Z:51 (= number of protons)Neutrons N:75Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.4705882352941 (= neutron-proton ratio)Neutron excess (N-Z):24Excitation energy:17.7(3) keVIsotopic mass:125.90725(3) u (atomic weight of Antimony-126m1)Nuclide mass:125.8792741 u (calculated nuclear mass without electrons)Mass excess:-86.39607 MeVMass defect:1.141695332 u (per nucleus)Nuclear binding energy:1063.48235159 MeV (per nucleus) 8.44033612 MeV (average binding energy per nucleon)Half-life:19.15(8) minDecay constant λ:0.00060326125375104 s-1Specific activity α:2.885397135703 × 10+18 Bq g-1 77983706.370359 Ci g-1Spin and parity: (nuclear angular momentum)(5+)
Radioactive Decay
Half-life T½ = 19.15(8) min (minutes) respectively 1.149 × 103 seconds s.
Decay mode
Daughter
Probability
Decay energy
γ energy (intensity)
β-
126Te
86(4) %
Iso
126Sb
14(4) %
Nuclear Isomers
Nuclear isomers or excited states with the activation energy in keV related to the ground state.
The following table shows the atomic nuclei that are isotonic (same neutron number N = 75) and isobaric (same nucleon number A = 126) with Antimony-126m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
