Germanium-90

Properties and data of the isotope ⁹⁰Ge.

Contents

See also: List of individual Germanium isotopes (and general data sources).

General data

Name of the isotope:Germanium-90; Ge-90Symbol:⁹⁰Ge or 9032GeMass number A:90 (= number of nucleons)Atomic number Z:32 (= number of protons)Neutrons N:58Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.8125 (= neutron-proton ratio)Neutron excess (N-Z):26Isotopic mass:89.96863(54) u (atomic weight of Germanium-90)Nuclide mass:89.951076 u (calculated nuclear mass without electrons)Mass excess:-29.22097 MeVMass defect:0.78433615199999 u (per nucleus)Nuclear binding energy:730.60441957 MeV (per nucleus)
8.11782688 MeV (average binding energy per nucleon)Separation energy:S_N = 3.56(64) MeV (first neutron)Half-life:635 nsDecay constant λ:1091570.3630865 s^-1Specific activity α:7.306536040341 × 10⁺²⁷ Bq g^-1
1.974739470362 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:2010

Radioactive Decay

Half-life T_½ = 635 ns respectively 6.35 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	⁹⁰As	?	12.11(64) MeV
β^-, n	⁸⁹As	?	9.51(58) MeV
β^-, 2n	⁸⁸As	?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 58) and isobaric (same nucleon number A = 90) with Germanium-90. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 58	Isobar A = 90
32	⁹⁰Ge	⁹⁰Ge
33	⁹¹As	⁹⁰As
34	⁹²Se	⁹⁰Se
35	⁹³Br	⁹⁰Br
36	⁹⁴Kr	⁹⁰Kr
37	⁹⁵Rb	⁹⁰Rb
38	⁹⁶Sr	⁹⁰Sr
39	⁹⁷Y	⁹⁰Y
40	⁹⁸Zr	⁹⁰Zr
41	⁹⁹Nb	⁹⁰Nb
42	¹⁰⁰Mo	⁹⁰Mo
43	¹⁰¹Tc	⁹⁰Tc
44	¹⁰²Ru	⁹⁰Ru
45	¹⁰³Rh	⁹⁰Rh
46	¹⁰⁴Pd	⁹⁰Pd
47	¹⁰⁵Ag
48	¹⁰⁶Cd
49	¹⁰⁷In
50	¹⁰⁸Sn
51	¹⁰⁹Sb
52	¹¹⁰Te
53	¹¹¹I
54	¹¹²Xe
55	¹¹³Cs
56	¹¹⁴Ba