See also: List of individual Germanium isotopes (and general data sources).
General data
Name of the isotope:Germanium-87; Ge-87Symbol:87Ge or 8732GeMass number A:87 (= number of nucleons)Atomic number Z:32 (= number of protons)Neutrons N:55Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.71875 (= neutron-proton ratio)Neutron excess (N-Z):23Isotopic mass:86.95268(32) u (atomic weight of Germanium-87)Nuclide mass:86.935126 u (calculated nuclear mass without electrons)Mass excess:-44.0783 MeVMass defect:0.77429140400001 u (per nucleus)Nuclear binding energy:721.24779708 MeV (per nucleus) 8.29020456 MeV (average binding energy per nucleon)Separation energy:SN = 2.75(53) MeV (first neutron) SP = 17.29(50) MeV (first proton)Half-life:0.14 sDecay constant λ:4.9510512897139 s-1Specific activity α:3.428983186790 × 10+22 Bq g-1 926752212646.05 Ci g-1Spin and parity: (nuclear angular momentum)(5/2+)Year of discovery:1997
Radioactive Decay
Half-life T½ = 0.14 s respectively 1.4 × 10-1 seconds s.
Decay mode
Daughter
Probability
Decay energy
γ energy (intensity)
β-
87As
100 %
11.54(30) MeV
β-, n
86As
?
6.81(30) MeV
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 55) and isobaric (same nucleon number A = 87) with Germanium-87. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
