Germanium (Ge)

Lustrous hard metalloid element, belongs to group 14 of the periodic table. Forms a large number of organometallic compounds. Predicted by Mendeleev in 1871, it was actually found in 1886 by Winkler.

Atomic Number	32
Atomic Weight	72.63
Mass Number	74

Group	14
Period	4
Block	p

Protons	32 p⁺
Neutrons	42 n⁰
Electrons	32 e^-

Properties

Energy
Atomic Radius	125 pm 234 pm
Molar Volume	13.6 cm³/mol
Covalent Radius	121 pm 111 pm 114 pm 120 pm
Metallic Radius	124 pm 144 pm
Ionic Radius	73 pm 39 pm 53 pm
Crystal Radius	87 pm 53 pm 67 pm
Van der Waals Radius	210 pm 427 pm 211 pm 244 pm 211 pm 428 pm
Density	5.3234 g/cm³ 5,600 kg/m³
Proton Affinity
Electron Affinity	1.232712 eV/particle
Ionization Energy	7.899435 eV/particle 15.93461 eV/particle 34.0576 eV/particle 45.715 eV/particle 90.5 eV/particle 115.9 eV/particle 144.9 eV/particle 176.4 eV/particle 212.5 eV/particle 252.1 eV/particle 286 eV/particle 326 eV/particle 367 eV/particle 407 eV/particle 527.9 eV/particle 567.29 eV/particle 609.06 eV/particle 662.8 eV/particle 710 eV/particle 744 eV/particle 837.1 eV/particle 880.444 eV/particle 2,180.1 eV/particle 2,304 eV/particle 2,439 eV/particle 2,575 eV/particle 2,737.2 eV/particle 2,881.9 eV/particle 3,074 eV/particle 3,194.293 eV/particle 13,557.4202 eV/particle 14,119.429 eV/particle

Heat of Vaporization	328 kJ/mol
Heat of Fusion	36.8 kJ/mol
Heat of Formation	372 kJ/mol
Electrons
Electron Shells	2, 8, 18, 4

Valence Electrons	4

Electron Configuration	[Ar] 3d¹⁰ 4s² 4p²

Oxidation States	-4, -3, -2, -1, 0, 1, 2, 3, 4
Electronegativity	11.8 eV/particle 0.1895892 2.01
Electrophilicity	1.5636638275958255 eV/particle
Phases
Phase	Solid
Gas Phase
Boiling Point	3,106.15 K
Melting Point	1,211.4 K
Critical Pressure
Critical Temperature	9,802.15 K
Triple Point
Visual
Color	Gray #ff1493 #668f8f #668f8f
Appearance	grayish-white
Refractive Index
Thermodynamic Properties
Thermal Conductivity	60.2 W/(m K)
Thermal Expansion	0.000006 1/K
Molar Heat Capacity	23.222 J/(mol K)
Specific Heat Capacity	0.32 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Semiconductor
Electrical Conductivity	0.002 MS/m
Electrical Resistivity	0.0005 m Ω
Superconducting Point
Magnetism
Type	diamagnetic
Magnetic Susceptibility (Mass)	-0.0000000015 m³/Kg
Magnetic Susceptibility (Molar)	-0.000000000109 m³/mol
Magnetic Susceptibility (Volume)	-0.00000798
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal Structure	Face Centered Cubic (DIA)
Lattice Constant	5.66 Å
Lattice Angles	π/2, π/2, π/2
Mechanical Properties
Hardness	6 MPa
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound	5,400 m/s
Classification
Category	Metalloids, Metalloids
CAS Group	IVB
IUPAC Group	IVA
Glawe Number	84
Mendeleev Number	89
Pettifor Number	84
Geochemical Class
Goldschmidt Class	chalcophile
Other
Gas Basicity
Dipole Polarizability	40 ± 1 a₀
C6 Dispersion Coefficient	354 a₀ 365 a₀
Allotropes
Neutron Cross Section	2.2
Neutron Mass Absorption	0.0011
Quantum Numbers	3P0
Space Group	225 (Fm_3m)

Isotopes of Germanium

Stable Isotopes	5
Unstable Isotopes	28
Radioactive Isotopes	28

⁵⁸Ge

Abundance
Relative Atomic Mass	57.991863 ± 0.000537 Da
Mass Number	58
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year
Parity	+

⁵⁸Ge Decay Modes

Decay Mode	Intensity
2p (2-proton emission)	%

⁵⁹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	58.982426 ± 0.000429 Da
Mass Number	59
G-Factor
Half Life	13.3 ± 1.7 ms
Spin	7/2
Quadrupole Moment
Discovery Year	2015
Parity	-

⁵⁹Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	93%
2p (2-proton emission)	0.2%

⁶⁰Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	59.970445 ± 0.000322 Da
Mass Number	60
G-Factor	0
Half Life	21 ± 6 ms
Spin	0
Quadrupole Moment	0
Discovery Year	2005
Parity	+

⁶⁰Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	100%
2p (2-proton emission)	14%

⁶¹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	60.963725 ± 0.000322 Da
Mass Number	61
G-Factor
Half Life	40.7 ± 0.4 ms
Spin	3/2
Quadrupole Moment
Discovery Year	1987
Parity	-

⁶¹Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	87%

⁶²Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	61.954761 ± 0.00015 Da
Mass Number	62
G-Factor	0
Half Life	82.5 ± 1.4 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1991
Parity	+

⁶²Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	%

⁶³Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	62.949628 ± 0.00004 Da
Mass Number	63
G-Factor
Half Life	153.6 ± 1.1 ms
Spin	3/2
Quadrupole Moment
Discovery Year	1991
Parity	-

⁶³Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	%

⁶⁴Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	63.941689912 ± 0.000004 Da
Mass Number	64
G-Factor	0
Half Life	63.7 ± 2.5 s
Spin	0
Quadrupole Moment	0
Discovery Year	1972
Parity	+

⁶⁴Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁶⁵Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	64.939368136 ± 0.000002323 Da
Mass Number	65
G-Factor
Half Life	30.9 ± 0.5 s
Spin	3/2
Quadrupole Moment
Discovery Year	1972
Parity	-

⁶⁵Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	0.011%

⁶⁶Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	65.933862124 ± 0.000002577 Da
Mass Number	66
G-Factor	0
Half Life	2.26 ± 0.05 h
Spin	0
Quadrupole Moment	0
Discovery Year	1950
Parity	+

⁶⁶Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁶⁷Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	66.932716999 ± 0.000004636 Da
Mass Number	67
G-Factor
Half Life	18.9 ± 0.3 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1950
Parity	-

⁶⁷Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁶⁸Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	67.928095305 ± 0.000002014 Da
Mass Number	68
G-Factor	0
Half Life	271.05 ± 0.08 d
Spin	0
Quadrupole Moment	0
Discovery Year	1948
Parity	+

⁶⁸Ge Decay Modes

Decay Mode	Intensity
ϵ (electron capture)	100%

⁶⁹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	68.927964467 ± 0.000001414 Da
Mass Number	69
G-Factor	0.294 ± 0.0028
Half Life	39.05 ± 0.1 h
Spin	5/2
Quadrupole Moment	0.114 ± 0.007
Discovery Year	1938
Parity	-

⁶⁹Ge Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

⁷⁰Ge

Abundance	20.52 ± 0.19
Relative Atomic Mass	69.924248542 ± 0.00000088 Da
Mass Number	70
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1923
Parity	+

⁷¹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	70.92495212 ± 0.000000874 Da
Mass Number	71
G-Factor
Half Life	11.43 ± 0.03 d
Spin	1/2
Quadrupole Moment	0
Discovery Year	1941
Parity	-

⁷¹Ge Decay Modes

Decay Mode	Intensity
ϵ (electron capture)	100%

⁷²Ge

Abundance	27.45 ± 0.15
Relative Atomic Mass	71.922075824 ± 0.000000081 Da
Mass Number	72
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1923
Parity	+

⁷³Ge

Abundance	7.76 ± 0.08
Relative Atomic Mass	72.923458954 ± 0.000000061 Da
Mass Number	73
G-Factor	-0.19516444444444 ± 0.000011111111111111
Half Life
Spin	9/2
Quadrupole Moment	-0.196 ± 0.001
Discovery Year	1933
Parity	+

⁷⁴Ge

Abundance	36.52 ± 0.12
Relative Atomic Mass	73.92117776 ± 0.000000013 Da
Mass Number	74
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1923
Parity	+

⁷⁵Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	74.92285837 ± 0.000000055 Da
Mass Number	75
G-Factor	1.018 ± 0.01
Half Life	82.78 ± 0.04 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1939
Parity	-

⁷⁵Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁷⁶Ge

Abundance	Radioactive ☢️ 7.75 ± 0.12
Relative Atomic Mass	75.921402725 ± 0.000000019 Da
Mass Number	76
G-Factor	0
Half Life	1.88 ± 0.08 Zy
Spin	0
Quadrupole Moment	0
Discovery Year	1933
Parity	+

⁷⁶Ge Decay Modes

Decay Mode	Intensity
2β⁻ (double β⁻ decay)	100%

⁷⁷Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	76.923549843 ± 0.000000056 Da
Mass Number	77
G-Factor
Half Life	11.211 ± 0.003 h
Spin	7/2
Quadrupole Moment
Discovery Year	1939
Parity	+

⁷⁷Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁷⁸Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	77.922852911 ± 0.000003795 Da
Mass Number	78
G-Factor	0
Half Life	88 ± 1 m
Spin	0
Quadrupole Moment	0
Discovery Year	1953
Parity	+

⁷⁸Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁷⁹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	78.925359506 ± 0.000039893 Da
Mass Number	79
G-Factor
Half Life	18.98 ± 0.03 s
Spin	1/2
Quadrupole Moment	0
Discovery Year	1970
Parity

⁷⁹Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁸⁰Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	79.925350773 ± 0.000002205 Da
Mass Number	80
G-Factor	0
Half Life	29.5 ± 0.4 s
Spin	0
Quadrupole Moment	0
Discovery Year	1972
Parity	+

⁸⁰Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁸¹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	80.928832941 ± 0.000002205 Da
Mass Number	81
G-Factor
Half Life	9 ± 2 s
Spin	9/2
Quadrupole Moment
Discovery Year	1972
Parity	+

⁸¹Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁸²Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	81.929774031 ± 0.000002405 Da
Mass Number	82
G-Factor	0
Half Life	4.31 ± 0.19 s
Spin	0
Quadrupole Moment	0
Discovery Year	1972
Parity	+

⁸²Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

⁸³Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	82.9345391 ± 0.000002604 Da
Mass Number	83
G-Factor
Half Life	1.85 ± 0.06 s
Spin	5/2
Quadrupole Moment
Discovery Year	1972
Parity	+

⁸³Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%

⁸⁴Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	83.93757509 ± 0.000003403 Da
Mass Number	84
G-Factor	0
Half Life	951 ± 9 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1972
Parity	+

⁸⁴Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	10.6%

⁸⁵Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	84.942969658 ± 0.000004003 Da
Mass Number	85
G-Factor
Half Life	495 ± 5 ms
Spin	3/2
Quadrupole Moment
Discovery Year	1991
Parity	+

⁸⁵Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	17.2%
2n (2-neutron emission)	%

⁸⁶Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	85.946967 ± 0.00047 Da
Mass Number	86
G-Factor	0
Half Life	221.6 ± 11 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1994
Parity	+

⁸⁶Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	45%

⁸⁷Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	86.953204 ± 0.000322 Da
Mass Number	87
G-Factor
Half Life	103 ± 4 ms
Spin	5/2
Quadrupole Moment
Discovery Year	1997
Parity	+

⁸⁷Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%
2n (2-neutron emission)	%

⁸⁸Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	87.957574 ± 0.000429 Da
Mass Number	88
G-Factor	0
Half Life	61 ± 6 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1997
Parity	+

⁸⁸Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	%
2n (2-neutron emission)	%

⁸⁹Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	88.96453 ± 0.000429 Da
Mass Number	89
G-Factor
Half Life
Spin	3/2
Quadrupole Moment
Discovery Year	1997
Parity	+

⁸⁹Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	%
β⁻ n (β⁻-delayed neutron emission)	%
2n (2-neutron emission)	%

⁹⁰Ge

Abundance	Radioactive ☢️
Relative Atomic Mass	89.969436 ± 0.000537 Da
Mass Number	90
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	2010
Parity	+

⁹⁰Ge Decay Modes

Decay Mode	Intensity
β⁻ (β⁻ decay)	%
β⁻ n (β⁻-delayed neutron emission)	%
2n (2-neutron emission)	%

History

In 1869, Dmitri Mendeleev predicted its existence and some of its properties based on its position on his periodic table and called the element eka-silicon. In 1886, Clemens Winkler found the new element along with silver and sulfur, in a rare mineral called argyrodite. The first silicon-germanium alloys were obtained in 1955. From the Latin word Germania, Germany

Discoverers	Clemens Winkler
Discovery Location	Germany
Discovery Year	1886
Etymology (Name Origin)	Latin: Germania (Germany).
Pronunciation	jer-MAY-ni-em (English)

Germanium is not known to be toxic

Germanium and the oxide are transparent to infrared radiation

Uses

The most common use of germanium is as a semiconductor in electronics. Germanium is used in transistors and in integrated circuits. It is used as an alloying agent and as a catalyst. It is also used in infrared spectroscopes and infrared detectors. Widely used in semiconductors. It is a good semiconductor when combined with tiny amounts of phosphorus, arsenic, gallium, and antimony.

Sources

Obtained from refining copper, zinc and lead.

Abundance
Abundance in Earth's crust	1.5 mg/kg
Abundance in Oceans	0.00005 mg/L
Abundance in Human Body
Abundance in Meteor	0.0021 %
Abundance in Sun	0.00002 %
Abundance in Universe	0.00002 %

Nuclear Screening Constants

1	s	0.7063
2	p	3.9178
2	s	8.6352
3	d	15.7487
3	p	14.9864
3	s	14.2103
4	p	25.2196
4	s	23.9564

Germanium on ChemicalAid

Art & Architecture Thesaurus ID	300380222
Australian Educational Vocabulary ID	scot/3524
BNCF Thesaurus ID	21205
Bibliothèque nationale de France ID	122010330
Brockhaus Enzyklopädie online ID	germanium
CAS Registry Number	7440-56-4
ChEBI ID	30441
ChemSpider ID	4885606
DSSTOX compound identifier	DTXCID5031056
DSSTox substance ID	DTXSID8052483
Den Store Danske ID	germanium
ECHA Substance Infocard ID	100.028.331
Elhuyar ZTH ID	024624
Encyclopædia Universalis ID	germanium
Freebase ID	/m/025rs3d
French Vikidia ID	Germanium
GND ID	4135644-5
Gran Enciclopèdia Catalana ID	0111877
Great Russian Encyclopedia Online ID	2354288
HSDB ID	2118
InChI	InChI=1S/Ge
InChIKey	GNPVGFCGXDBREM-UHFFFAOYSA-N
KBpedia ID	Germanium
Library of Congress authority ID	sh85054449
MeSH descriptor ID	D005857
NDF-RT ID	N0000176163
NKCR AUT ID	ph927791
Namuwiki ID	저마늄
National Diet Library ID	00562424
National Library of Israel J9U ID	987007565426605171
OmegaWiki Defined Meaning	159569
OpenAlex ID	C550623735
OpenAlex ID	C2909614401
PSH ID	5798
PubChem CID	6326954
RxNorm ID	4784
Store norske leksikon ID	germanium
Treccani ID	germanio
UMLS CUI	C0017479
UNII	00072J7XWS
WordNet 3.1 Synset ID	14662695-n
YSO ID	22858
ZVG number	8270

Germanium (Ge)

Properties

Isotopes of Germanium

58Ge

58Ge Decay Modes

59Ge

59Ge Decay Modes

60Ge

60Ge Decay Modes

61Ge

61Ge Decay Modes

62Ge

62Ge Decay Modes

63Ge

63Ge Decay Modes

64Ge

64Ge Decay Modes

65Ge

65Ge Decay Modes

66Ge

66Ge Decay Modes

67Ge

67Ge Decay Modes

68Ge

68Ge Decay Modes

69Ge

69Ge Decay Modes

70Ge

71Ge

71Ge Decay Modes

72Ge

73Ge

74Ge

75Ge

75Ge Decay Modes

76Ge

76Ge Decay Modes

77Ge

77Ge Decay Modes

78Ge

78Ge Decay Modes

79Ge

79Ge Decay Modes

80Ge

80Ge Decay Modes

81Ge

81Ge Decay Modes

82Ge

82Ge Decay Modes

83Ge

83Ge Decay Modes

84Ge

84Ge Decay Modes

85Ge

85Ge Decay Modes

86Ge

86Ge Decay Modes

87Ge

87Ge Decay Modes

88Ge

88Ge Decay Modes

89Ge

89Ge Decay Modes

90Ge

90Ge Decay Modes