Germanium-73

Properties and data of the isotope ⁷³Ge.

Contents

General Data

Parent Nuclides

NMR Data

Isotones und Isobares

Literature

Germanium-73 is a stable isotope of the chemical element germanium, comprising 7.76 % of terrestrial germanium deposits. The atomic nucleus of this nuclide contains the element-specific 32 protons and 41 neutrons; the sum of these nuclear constituents results in a mass number of 73.

The discovery of germanium-73 using a magnetic spectrograph was reported in 1933 [1].

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

General data

Name of the isotope:Germanium-73; Ge-73Symbol:⁷³Ge or 7332GeMass number A:73 (= number of nucleons)Atomic number Z:32 (= number of protons)Neutrons N:41Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.28125 (= neutron-proton ratio)Neutron excess (N-Z):9Isotopic mass:72.92345895(6) u (atomic weight of Germanium-73)Nuclide mass:72.905905 u (calculated nuclear mass without electrons)Mass excess:-71.29753 MeVMass defect:0.68220363 u (per nucleus)Nuclear binding energy:635.46858812 MeV (per nucleus)
8.70504915 MeV (average binding energy per nucleon)Separation energy:S_N = 6.78294(5) MeV (first neutron)
S_P = 9.9982(8) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)9/2+Magnetic dipole moment:μ(μ_N) = -0.87824(5)Charge radius:4.0632(14) femtometer fmYear of discovery:1933

Parent Nuclides

Direct parent isotopes are: ⁷³As, ⁷³Ga.

Occurrence

Comparison of the natural Germanium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Germanium Isotopic mixture	72.630 u	100 %
Isotope ⁷⁰Ge	69.924249(6) u	20.52(19) %	stable	0+
Isotope ⁷²Ge	71.9220758(5) u	27.45(15) %	stable	0+
Isotope ⁷⁴Ge	73.92117776(9) u	36.52(12) %	stable	0+
Isotope ⁷⁶Ge	75.9214027(2) u	7.75(12) %	1.926(94) × 10²¹ years	0+
Isotope ⁷³Ge	72.92345895(6) u	7.76(8) %	stable	9/2+

NMR data

Nuclear magnetic properties and parameters of the NMR active Nuclide ⁷³Ge

Isotope:⁷³Ge-NMRQuantity:7.76(8) %Spin:9/2+Nuclearmagnetic moment
μ/μ_N:-0.87824(5)Gyromagnetic ratio γ:-0.9360303 · 10⁷ rad T^-1 s^-1
-1.48974 MHz T^-1Nuclear g-factor:g_l = -0.19516444444444Quadrupole moment Q:-0.196(1) barn (100 fm²)Line width parameter (factor):l = 28.46 fm⁴Resonance frequency:v₀ = 1.4897 MHz at 1 TRelative Sensitivity:[related to ¹H = 1.000]:
0.00141 (H₀ = const.)
1.1547 (v₀ = const.)
0.000109 (at natural abundance)
relative receptivity as compared to ¹³C:
0.642 (at natural abundance)
8.31 (enriched)Reference compound:
(conditions)Pure Tetramethylgermanium (CH₃)₄Ge.Frequency ratio:Ξ(⁷³Ge) = 3.488315 % [based on the reference substance]

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
^73m1Ge	13.2845(15) keV	0.499(11) s	5/2+
^73m2Ge	66.725(9) keV	499(11) ms	1/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 41) and isobaric (same nucleon number A = 73) with Germanium-73. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 41	Isobar A = 73
21	⁶²Sc
22	⁶³Ti
23	⁶⁴V
24	⁶⁵Cr
25	⁶⁶Mn
26	⁶⁷Fe	⁷³Fe
27	⁶⁸Co	⁷³Co
28	⁶⁹Ni	⁷³Ni
29	⁷⁰Cu	⁷³Cu
30	⁷¹Zn	⁷³Zn
31	⁷²Ga	⁷³Ga
32	⁷³Ge	⁷³Ge
33	⁷⁴As	⁷³As
34	⁷⁵Se	⁷³Se
35	⁷⁶Br	⁷³Br
36	⁷⁷Kr	⁷³Kr
37	⁷⁸Rb	⁷³Rb
38	⁷⁹Sr	⁷³Sr
39	⁸⁰Y
40	⁸¹Zr
41	⁸²Nb
42	⁸³Mo
44	⁸⁵Ru

External data and identifiers

Adopted Levels, Gammas:NuDat 73Ge

Literature and References

[1] - Kenneth T. Bainbridge:
The masses of atoms and the structure of atomic nuclei.
In: Journal of the Franklin Institute, 215, 5, (1933), DOI 10.1016/S0016-0032(33)90167-2.