Ge 32

Germanium (Ge)

metalloid

Period: 4 Group: 14 Block: p

Solid

Standard Atomic Weight

Electron configuration

[Ar] 4s² 3d¹⁰ 4p²

Melting point

938.25 °C (1211.4 K)

Boiling point

2832.85 °C (3106 K)

Density

5323.4 kg/m³

Oxidation states

−4, −3, −2, −1, 0, +1, +2, +3, +4

Electronegativity (Pauling)

2.01

Ionization energy (1st)

Discovery year

1886

Atomic radius

125 pm

Details

Name origin Latin: Germania (Germany).

Discovery country Germany

Discoverers Clemens Winkler

Germanium is a hard, brittle metalloid in group 14, chemically intermediate between silicon and tin. It is a covalent semiconductor with a narrow band gap and forms stable compounds mainly in the +4 and +2 oxidation states. The element is not mined as a principal ore in most operations; it is commonly recovered as a by-product from zinc processing and from some coal-derived materials. Its technological importance rests on infrared optics, fiber-optic materials, semiconductor devices, and specialty catalysts.

The element is a gray-white metalloid. In pure state, the element is crystalline and brittle, retaining its luster in air at room temperature. It is a very important semiconductor. Zone-refining techniques have led to production of crystalline germanium for semiconductor use with an impurity of only one part in 1010.

The name derives from the Latin germania for Germany. It was discovered and isolated by the German chemist Clemens-Alexander Winkler in 1886 in the mineral argyrodite (GeS2×4Ag2S).

First proposed to exist by Dmitri Mendeleyev in 1871 based on gaps in his newly created Periodic Table of Elements, germanium was discovered by the German chemist Clemens Winkler in the mineral argyrodite (Ag8GeS6) in 1886. Today, germanium is primarily obtained from the smelting of zinc ores and from the byproducts of burning certain types of coal.

From the Latin word Germania, Germany. Mendeleev predicted the existence of Germanium in 1871 as ekasilicon, and the element was discovered by Winkler in 1886.

Read about Germanium on Wikipedia

Images

Properties

Physical

Atomic radius (empirical) 125 pm

Covalent radius 120 pm

Van der Waals radius 211 pm

Metallic radius 124 pm

Density

Molar volume 0.0136 L/mol

Phase at STP solid

Melting point 938.25 °C

Boiling point 2832.85 °C

Thermal conductivity 60.2 W/(m·K)

Specific heat capacity 0.32 J/(g·K)

Molar heat capacity 23.222 J/(mol·K)

Crystal structure diamond

Chemical

Electronegativity (Pauling) 2.01

Electronegativity (Allen) 1.994

Electron affinity

Ionization energy (1st)

Ionization energy (2nd)

Ionization energy (3rd)

Ionization energy (4th)

Ionization energy (5th)

Oxidation states −4, −3, −2, −1, 0, +1, +2, +3, +4

Valence electrons 4

Electron configuration

Electron configuration (semantic)

Thermodynamic

Critical point (temperature) 9529 °C

Heat of fusion 0.38285744 eV

Heat of vaporization 3.420221 eV

Heat of sublimation 3.907343 eV

Heat of atomization 3.907343 eV

Atomization enthalpy

Nuclear

Stable isotopes 5

Discovery year 1886

Abundance

Abundance (Earth's crust) 1.5 mg/kg

Abundance (ocean)

Reactivity

N/A

Crystal Structure

Lattice constant a 566 pm

Electronic Structure

Electrons per shell 2, 8, 18, 4

Identifiers

CAS number 7440-56-4

Term symbol

InChI InChI=1S/Ge

InChI Key GNPVGFCGXDBREM-UHFFFAOYSA-N

Electron Configuration Measured

Ion charge

Protons 32

Electrons 32

Charge Neutral

Configuration Ge: 3d¹⁰ 4s² 4p²

[Ar] 3d¹⁰ 4s² 4p²

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p²

Orbital diagram

↑↓

2/2

↑↓

2/2

↑↓

6/6

↑↓

2/2

↑↓

6/6

↑↓

2/2

↑↓

10/10

↑

2/6 2↑

Total electrons: 32 Unpaired: 2

Atomic model

Protons 32

Neutrons 42

Electrons 32

Mass number 74

Stability Stable

Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.

Schematic atomic model, not to scale.

Atomic Fingerprint

Emission / Absorption Spectrum

Emission Visible: 380–750 nm

Isotope Distribution

Mass number	Atomic mass (u)	Natural abundance	Half-life
70 Stable	69.92424875 ± 0.0000009	20.5700%	Stable
72 Stable	71.922075826 ± 0.000000081	27.4500%	Stable
73 Stable	72.923458956 ± 0.000000061	7.7500%	Stable
74 Stable	73.921177761 ± 0.000000013	36.5000%	Stable

Measured

Phase / State

Solid 25 °C (298.15 K)

Reason: 913.3 °C below melting point (938.25 °C)

Melting point 938.25 °C

Boiling point 2832.85 °C

Below melting by 913.3 °C

0 K Current temperature: 25 °C 6000 K

Phase timeline

Schematic, not to scale

Solid

Liquid

Gas

Melting

Boiling

25°C

Solid

Liquid

Gas

Current

Phase transition points

Melting point Literature

938.25 °C

Boiling point Literature

2832.85 °C

Current phase Calculated
Solid

Transition energies

Heat of fusion Literature

0.38285744 eV

Energy required to melt 1 mol at melting point

Heat of vaporization Literature

3.420221 eV

Energy required to vaporize 1 mol at boiling point

Heat of sublimation Literature

3.907343 eV

Energy required to sublime 1 mol at sublimation point

Density

Reference density Literature

5323.4 kg/m³

At standard conditions

Current density Calculated

5323.4 kg/m³

At standard conditions

Advanced

Critical point Literature

9529 °C

Atomic Spectra

Showing 10 of 32 Atomic Spectra. Sorted by ion charge (ascending).

Lines Holdings ?

Ion	Charge	Total lines	Transition probabilities	Level designations
Ge I	0	224	26	223
Ge II	+1	149	20	149
Ge III	+2	55	0	0
Ge IV	+3	27	0	0
Ge V	+4	37	0	0

NIST Lines Holdings →

Levels Holdings ?

Ion	Charge	Levels
Ge I	0	621
Ge II	+1	129
Ge III	+2	48
Ge IV	+3	55
Ge V	+4	102
Ge VI	+5	105
Ge VII	+6	168
Ge VIII	+7	2
Ge IX	+8	2
Ge X	+9	2

NIST Levels Holdings →

32 Ge 72.63

Germanium — Atomic Orbital Visualizer

[Ar]4s23d104p2

Energy levels 2 8 18 4

Oxidation states -4, -3, -2, -1, 0, +1, +2, +3, +4

HOMO 4p n=4 · l=1 · m=-1

Germanium — Atomic Orbital Visualizer Preview

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32 Ge 72.63

Germanium — Crystal Structure Visualizer

Face-Centered Cubic · Pearson cF8

Experimental

Pearson cF8

Coord. № 4

Packing 34.000%

Germanium — Crystal Structure Visualizer Preview

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Ionic Radii

Charge	Coordination	Spin	Radius
+2	6	N/A	73 pm
+4	4	N/A	39 pm
+4	6	N/A	53 pm

Compounds

72.630 u

Ge+4

72.630 u

67.928 u

68.928 u

72.923 u

70.925 u

74.923 u

76.924 u

66.933 u

77.923 u

65.934 u

73.921 u

71.922 u

69.924 u

75.921 u

Isotopes (4)

Mass number	Atomic mass (u)	Natural abundance	Half-life	Decay mode
70 Stable	69.92424875 ± 0.0000009	20.5700% ± 0.2700%	Stable	stable
72 Stable	71.922075826 ± 0.000000081	27.4500% ± 0.3200%	Stable	stable
73 Stable	72.923458956 ± 0.000000061	7.7500% ± 0.1200%	Stable	stable
74 Stable	73.921177761 ± 0.000000013	36.5000% ± 0.2000%	Stable	stable

70 Stable

Atomic mass (u) 69.92424875 ± 0.0000009

Natural abundance 20.5700% ± 0.2700%

Half-life Stable

Decay mode

stable

72 Stable

Atomic mass (u) 71.922075826 ± 0.000000081

Natural abundance 27.4500% ± 0.3200%

Half-life Stable

Decay mode

stable

73 Stable

Atomic mass (u) 72.923458956 ± 0.000000061

Natural abundance 7.7500% ± 0.1200%

Half-life Stable

Decay mode

stable

74 Stable

Atomic mass (u) 73.921177761 ± 0.000000013

Natural abundance 36.5000% ± 0.2000%

Half-life Stable

Decay mode

stable

Spectral Lines

Showing 50 of 57 Spectral Lines. Only spectral lines with measured intensity are shown by default.

Wavelength (nm)	Intensity	Ion stage	Type	Transition	Accuracy	Source
474.18054 nm	1000	Ge II	emission	4s2.5p 2P* → 4s2.5d 2D	Measured	NIST
481.46084 nm	1000	Ge II	emission	4s2.5p 2P* → 4s2.5d 2D	Measured	NIST
589.33885 nm	1000	Ge II	emission	4s2.5s 2S → 4s2.5p 2P*	Measured	NIST
602.10412 nm	500	Ge II	emission	4s2.5s 2S → 4s2.5p 2P*	Measured	NIST
517.86474 nm	200	Ge II	emission	4s2.4d 2D → 4s2.4f 2F*	Measured	NIST
607.834 nm	150	Ge II	emission	4s.4p.(3P).5s 4P → 4s.4p.(3P*).5p 4D	Measured	NIST
626.8068 nm	150	Ge II	emission	4s2.4f 2F* → 4s2.6g 2G	Measured	NIST
513.17516 nm	100	Ge II	emission	4s2.4d 2D → 4s2.4f 2F*	Measured	NIST
626.8341 nm	100	Ge II	emission	4s2.4f 2F* → 4s2.6g 2G	Measured	NIST
633.63765 nm	100	Ge II	emission	4s2.5p 2P* → 4s2.6s 2S	Measured	NIST
648.41813 nm	100	Ge II	emission	4s2.5p 2P* → 4s2.6s 2S	Measured	NIST
628.34518 nm	75	Ge II	emission	4s2.5d 2D → 4s2.6f 2F*	Measured	NIST
422.656259 nm	70	Ge I	emission	4s2.4p2 1S → 4s2.4p.5s 1P*	Measured	NIST
482.40972 nm	50	Ge II	emission	4s2.5p 2P* → 4s2.5d 2D	Measured	NIST
626.7136 nm	50	Ge II	emission	4s2.5d 2D → 4s2.6f 2F*	Measured	NIST
678.0486 nm	50	Ge II	emission	4s2.6p 2P* → 4s2.7d 2D	Measured	NIST
704.93692 nm	50	Ge II	emission	4s.4p2 2D → 4s2.5p 2P*	Measured	NIST
384.50994 nm	30	Ge II	emission	4s.4p2 4P → 4s2.5p 2P*	Measured	NIST
714.53898 nm	30	Ge II	emission	4s.4p2 2D → 4s2.5p 2P*	Measured	NIST
494.12769 nm	20	Ge II	emission	4s2.4d 2D → 4s2.6p 2P*	Measured	NIST
520.56488 nm	20	Ge II	emission	4s2.4f 2F* → 4s2.7g 2G	Measured	NIST
696.63205 nm	20	Ge II	emission	4s.4p2 2D → 4s2.5p 2P*	Measured	NIST
439.1656 nm	15	Ge II	emission	4s2.4f 2F* → 4s2.9g 2G	Measured	NIST
520.58372 nm	15	Ge II	emission	4s2.4f 2F* → 4s2.7g 2G	Measured	NIST
552.2987 nm	15	Ge II	emission	4s2.6p 2P* → 4s2.8d 2D	Measured	NIST
439.179 nm	10	Ge II	emission	4s2.4f 2F* → 4s2.9g 2G	Measured	NIST
466.2311 nm	10	Ge II	emission	4s2.5d 2D → 4s2.8f 2F*	Measured	NIST
468.582849 nm	10	Ge I	emission	4s2.4p2 1S → 4s2.4p.5s 3P*	Measured	NIST
493.40754 nm	10	Ge II	emission	4s2.4d 2D → 4s2.6p 2P*	Measured	NIST
517.84615 nm	10	Ge II	emission	4s2.4d 2D → 4s2.4f 2F*	Measured	NIST
569.19543 nm	9	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3D	Measured	NIST
580.2093 nm	9	Ge I	emission	4s2.4p.5s 1P* → 4s2.4p.6p 1D	Measured	NIST
556.47408 nm	8	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3S	Measured	NIST
560.70101 nm	8	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3P	Measured	NIST
565.596 nm	8	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3D	Measured	NIST
562.14256 nm	7	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 1P	Measured	NIST
733.0383 nm	7	Ge I	emission	4s2.4p.5p 1P → 4s2.4p.7d (1/2,3/2)*	Measured	NIST
738.4208 nm	7	Ge I	emission	4s2.4p.5p 3D → 4s2.4p.8s (1/2,1/2)*	Measured	NIST
526.58915 nm	6	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3P	Measured	NIST
551.32634 nm	6	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 1D	Measured	NIST
561.61353 nm	6	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3P	Measured	NIST
566.4226 nm	6	Ge I	emission	4s2.4p.5s 1P* → 4s2.4p.6p 1S	Measured	NIST
570.17765 nm	6	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 1P	Measured	NIST
580.1029 nm	6	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3D	Measured	NIST
655.74883 nm	6	Ge I	emission	4s2.4p.5s 1P* → 4s2.4p.6p 3D	Measured	NIST
713.0126 nm	6	Ge I	emission	4s2.4p.5p 3D → 4s2.4p.7d (3/2,5/2)*	Measured	NIST
740.2648 nm	6	Ge I	emission	4s2.4p.5p 1P → 4s2.4p.6d (3/2,3/2)*	Measured	NIST
518.4103 nm	5	Ge II	emission	4s2.5d 2D → 4s2.7f 2F*	Measured	NIST
566.4842 nm	5	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.(2P*<1/2>).4f 2[7/2]	Measured	NIST
571.78769 nm	5	Ge I	emission	4s2.4p.5s 3P* → 4s2.4p.6p 3D	Measured	NIST

Extended Properties

Covalent Radii (Extended)

Covalent radius (Pyykkö)

Covalent radius (Pyykkö, double)

Covalent radius (Pyykkö, triple)

Van der Waals Radii

Truhlar

Batsanov

Alvarez

UFF

MM3

Dreiding

Atomic & Metallic Radii

Atomic radius (Rahm)

Metallic radius (C12)

Numbering Scales

Mendeleev

Pettifor

Glawe

Electronegativity Scales

Ghosh

Miedema

Gunnarsson–Lundqvist

Robles–Bartolotti

Polarizability & Dispersion

Dipole polarizability

Dipole polarizability (unc.)

C₆

C₆ (Gould–Bučko)

Miedema Parameters

Miedema molar volume

Miedema electron density

Supply Risk & Economics

Production concentration

Relative supply risk

Political stability (top producer)

Phase Transitions & Allotropes

Melting point	1211.4 K
Boiling point	3106.15 K
Critical point (temperature)	9802.15 K

Oxidation State Categories

−2 extended

−3 extended

−4 main

−1 extended

+2 main

0 extended

+4 main

+1 extended

+3 extended

Advanced Reference Data

Screening Constants (8)

n	Orbital	σ
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

Crystal Radii Detail (3)

Charge	CN	r_crystal (pm)	Origin
2	VI	87	Ahrens (1952) ionic radius,
4	IV	53
4	VI	67	from r^3 vs V plots,

Isotope Decay Modes (50)

Isotope	Mode	Intensity
58	2p	—
59	B+	100%
59	B+p	93%
59	2p	0.2%
60	B+	100%
60	B+p	100%
60	2p	14%
61	B+	100%
61	B+p	87%
62	B+	100%

X‑ray Scattering Factors (506)

Energy (eV)	f₁	f₂
10	—	3.01183
10.1617	—	3.05548
10.3261	—	3.09976
10.4931	—	3.14468
10.6628	—	3.19025
10.8353	—	3.21825
11.0106	—	3.20755
11.1886	—	3.19689
11.3696	—	3.18626
11.5535	—	3.17568

Additional Data

Estimated Crustal Abundance

The estimated element abundance in the earth's crust.

1.5 milligrams per kilogram

References (1)

[5] Germanium https://education.jlab.org/itselemental/ele032.html

Estimated Oceanic Abundance

The estimated element abundance in the earth's oceans.

5×10-5 milligrams per liter

References (1)

[5] Germanium https://education.jlab.org/itselemental/ele032.html

Sources

Sources of this element.

The metal is found in

▸ argyrodite, a sulfide of germanium and silver;

▸ germanite, which contains 8 percent of the element;

▸ zinc ores;

▸ coal; and

▸ other minerals

The element is commercially obtained from the dust from smelters that process zinc ores. It is also recovered from combustion by-products of certain coals.

Germanium can be separated from other metals by fractional distillation of its volatile tetrachloride. These techniques permit the production of germanium of ultra-high purity.

References (1)

[6] Germanium https://periodic.lanl.gov/32.shtml

References

(9)

1 PubChem

Data deposited in or computed by PubChem

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2 Atomic Mass Data Center (AMDC), International Atomic Energy Agency (IAEA)

The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.

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3 IUPAC Commission on Isotopic Abundances and Atomic Weights (CIAAW)

Germanium

Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.

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4 IUPAC Periodic Table of the Elements and Isotopes (IPTEI)

The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.

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License note: Copyright (c) 2020 International Union of Pure and Applied Chemistry. The International Union of Pure and Applied Chemistry (IUPAC) contribution within Pubchem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.

5 Jefferson Lab, U.S. Department of Energy

Germanium

Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/

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License note: Please see citation and linking information: https://education.jlab.org/faq/index.html

6 Los Alamos National Laboratory, U.S. Department of Energy

Germanium

The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.

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7 NIST Physical Measurement Laboratory

Germanium

The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database

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8 PubChem Elements

Germanium

This section provides all form of data related to element Germanium.

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9 PubChem Elements

Germanium

The element property data was retrieved from publications.

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Last updated: May 1, 2026

Data verified: May 12, 2026

Content is reviewed against latest scientific data.