See also: List of individual Technetium isotopes (and general data sources).
General data
Name of the isotope:Technetium-111; Tc-111Symbol:111Tc or 11143TcMass number A:111 (= number of nucleons)Atomic number Z:43 (= number of protons)Neutrons N:68Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.5813953488372 (= neutron-proton ratio)Neutron excess (N-Z):25Isotopic mass:110.925899(11) u (atomic weight of Technetium-111)Nuclide mass:110.9023112 u (calculated nuclear mass without electrons)Mass excess:-69.02464 MeVMass defect:0.999791664 u (per nucleus)Nuclear binding energy:931.29993627 MeV (per nucleus) 8.39008952 MeV (average binding energy per nucleon)Separation energy:SN = 6.061(14) MeV (first neutron) SP = 11.771(26) MeV (first proton)Half-life:290(20) msDecay constant λ:2.390162691586 s-1Specific activity α:1.297613659009 × 10+22 Bq g-1 350706394326.92 Ci g-1Spin and parity: (nuclear angular momentum)(5/2+)Year of discovery:1988
Radioactive Decay
Half-life T½ = 290(20) ms respectively 2.90 × 10-1 seconds s.
Decay mode
Daughter
Probability
Decay energy
γ energy (intensity)
β-
111Ru
99.15 %
7.761(14) MeV
β-, n
110Ru
0.85(20) %
2.977(13) MeV
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 68) and isobaric (same nucleon number A = 111) with Technetium-111. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
