Gallium

Gallium (Ga)

Soft silvery metallic element, belongs to group 13 of the periodic table. The two stable isotopes are Ga-69 and Ga-71. Eight radioactive isotopes are known, all having short half-lives. Gallium Arsenide is used as a semiconductor. Corrodes most other metals by diffusing into their lattice. First identified by Francois Lecoq de Boisbaudran in 1875.
Atomic Number31
Atomic Weight69.723
Mass Number69
Group13
Period4
Blockp
Protons31 p+
Neutrons38 n0
Electrons31 e-
Gallium crystals.jpg Animated Bohr Model of Ga (Gallium) Enhanced Bohr Model of Ga (Gallium) Bohr Model: Ga (Gallium) Orbital Diagram of Ga (Gallium)

Properties

Atomic Radius
130 pm
Molar Volume
Covalent Radius
124 pm
Metallic Radius
125 pm
Ionic Radius
47 pm
Crystal Radius
61 pm
Van der Waals Radius
187 pm
Density
5.91 g/cm³
Energy
Proton Affinity
Electron Affinity
Ionization Energy
5.9993018 eV/particle
Heat of Vaporization
270.3 kJ/mol
Heat of Fusion
5.59 kJ/mol
Heat of Formation
271.96 kJ/mol
Electrons
Electron Shells2, 8, 18, 3
Valence Electrons3
Electron Configuration[Ar] 3d10 4s2 4p1
Oxidation States-5, -4, -3, -2, -1, 0, 1, 2, 3
Electronegativity
1.81
Electrophilicity
0.927762651403701 eV/particle
Phases
PhaseSolid
Gas Phase
Boiling Point
2,502.15 K
Melting Point
302.9146 K
Critical Pressure
Critical Temperature
Triple Point
302.9166 K
Visual
Color
Silver
Appearancesilver-white
Refractive Index
Thermodynamic Properties
Thermal Conductivity
28.1 W/(m K)
Thermal Expansion
0.00012 1/K
Molar Heat Capacity
26.03 J/(mol K)
Specific Heat Capacity
0.373 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
7.1 MS/m
Electrical Resistivity
0.00000014 m Ω
Superconducting Point
1.083 K
Magnetism
Typediamagnetic
Magnetic Susceptibility (Mass)
-0.000000003 m³/Kg
Magnetic Susceptibility (Molar)
-0.000000000209 m³/mol
Magnetic Susceptibility (Volume)
-0.0000177
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal StructureBase Centered Orthorhombic (ORC)
Lattice Constant
4.51 Å
Lattice Anglesπ/2, π/2, π/2
Mechanical Properties
Hardness
1.5 MPa
Bulk Modulus
Shear Modulus
Young Modulus
Poisson Ratio
Speed of Sound
2,740 m/s
Classification
CategoryPost-transition metals, Poor metals
CAS GroupIIIB
IUPAC GroupIIIA
Glawe Number79
Mendeleev Number83
Pettifor Number81
Geochemical Class
Goldschmidt Classchalcophile
Other
Gas Basicity
Dipole Polarizability
50 ± 3 a₀
C6 Dispersion Coefficient
498 a₀
Allotropes
Neutron Cross Section
2.9
Neutron Mass Absorption
0.0015
Quantum Numbers2P1/2
Space Group64 (Cmca)

Isotopes of Gallium

Stable Isotopes2
Unstable Isotopes31
Radioactive Isotopes26

56Ga

Abundance
Relative Atomic Mass
55.995878 ± 0.000537 Da
Mass Number56
G-Factor
Half Life
Spin3
Quadrupole Moment
Discovery Year
Parity+

56Ga Decay Modes
Decay ModeIntensity
p (proton emission)%

57Ga

Abundance
Relative Atomic Mass
56.983457 ± 0.000429 Da
Mass Number57
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year
Parity-

57Ga Decay Modes
Decay ModeIntensity
p (proton emission)%

58Ga

Abundance
Relative Atomic Mass
57.974729 ± 0.000322 Da
Mass Number58
G-Factor
Half Life
Spin2
Quadrupole Moment
Discovery Year
Parity+

58Ga Decay Modes
Decay ModeIntensity
p (proton emission)%

59Ga

Abundance
Relative Atomic Mass
58.963757 ± 0.000183 Da
Mass Number59
G-Factor
Half Life
Spin3/2
Quadrupole Moment
Discovery Year
Parity-

59Ga Decay Modes
Decay ModeIntensity
p (proton emission)%

60Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
59.957498 ± 0.000215 Da
Mass Number60
G-Factor
Half Life
72.4 ± 1.7 ms
Spin2
Quadrupole Moment
Discovery Year1995
Parity+

60Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)1.6%
β+α (β+-delayed α emission)0.023%

61Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
60.949398861 ± 0.000040787 Da
Mass Number61
G-Factor
Half Life
165.9 ± 2.5 ms
Spin3/2
Quadrupole Moment
Discovery Year1987
Parity-

61Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)0.25%

62Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
61.944189639 ± 0.000000684 Da
Mass Number62
G-Factor
0
Half Life
116.122 ± 0.021 ms
Spin0
Quadrupole Moment
0
Discovery Year1978
Parity+

62Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

63Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
62.939294194 ± 0.0000014 Da
Mass Number63
G-Factor
0.097866666666667 ± 0.00033333333333333
Half Life
32.4 ± 0.5 s
Spin3/2
Quadrupole Moment
0.212 ± 0.014
Discovery Year1965
Parity-

63Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

64Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
63.936840366 ± 0.000001533 Da
Mass Number64
G-Factor
0
Half Life
2.627 ± 0.012 m
Spin0
Quadrupole Moment
0
Discovery Year1953
Parity

64Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

65Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
64.932734424 ± 0.000000849 Da
Mass Number65
G-Factor
1.182 ± 0.002
Half Life
15.133 ± 0.028 m
Spin3/2
Quadrupole Moment
0.21 ± 0.015
Discovery Year1938
Parity-

65Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

66Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
65.931589766 ± 0.000001172 Da
Mass Number66
G-Factor
0
Half Life
9.304 ± 0.008 h
Spin0
Quadrupole Moment
0
Discovery Year1937
Parity+

66Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

67Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
66.928202276 ± 0.000001262 Da
Mass Number67
G-Factor
1.2329333333333 ± 0.00033333333333333
Half Life
3.2617 ± 0.0004 d
Spin3/2
Quadrupole Moment
0.197 ± 0.002
Discovery Year1938
Parity-

67Ga Decay Modes
Decay ModeIntensity
ϵ (electron capture)100%

68Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
67.927980161 ± 0.000001535 Da
Mass Number68
G-Factor
0.01174 ± 0.00007
Half Life
67.842 ± 0.016 m
Spin1
Quadrupole Moment
-0.0277 ± 0.0014
Discovery Year1937
Parity+

68Ga Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

69Ga

Abundance
60.108 ± 0.05
Relative Atomic Mass
68.925573528 ± 0.000001285 Da
Mass Number69
G-Factor
1.3433466666667 ± 0.00004
Half Life
Spin3/2
Quadrupole Moment
0.171 ± 0.002
Discovery Year1923
Parity-

70Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
69.926021914 ± 0.000001289 Da
Mass Number70
G-Factor
0.571 ± 0.002
Half Life
21.14 ± 0.05 m
Spin1
Quadrupole Moment
0.105 ± 0.007
Discovery Year1937
Parity+

70Ga Decay Modes
Decay ModeIntensity
β (β decay)99.59%
ϵ (electron capture)0.41%

71Ga

Abundance
39.892 ± 0.05
Relative Atomic Mass
70.924702554 ± 0.00000087 Da
Mass Number71
G-Factor
1.7068866666667 ± 0.00006
Half Life
Spin3/2
Quadrupole Moment
0.107 ± 0.001
Discovery Year1923
Parity-

72Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
71.926367452 ± 0.000000878 Da
Mass Number72
G-Factor
-0.044046666666667 ± 0.0000066666666666667
Half Life
14.025 ± 0.01 h
Spin3
Quadrupole Moment
0.53 ± 0.006
Discovery Year1939
Parity-

72Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

73Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
72.92517468 ± 0.0000018 Da
Mass Number73
G-Factor
0.13933333333333 ± 0.0013333333333333
Half Life
4.86 ± 0.03 h
Spin1/2
Quadrupole Moment
0
Discovery Year1949
Parity-

73Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

74Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
73.926945725 ± 0.000003214 Da
Mass Number74
G-Factor
0 ± 0.026666666666667
Half Life
8.12 ± 0.12 m
Spin3
Quadrupole Moment
0.55 ± 0.04
Discovery Year1956
Parity-

74Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

75Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
74.926504484 ± 0.00000072 Da
Mass Number75
G-Factor
1.2233333333333 ± 0.0026666666666667
Half Life
126 ± 2 s
Spin3/2
Quadrupole Moment
-0.285 ± 0.017
Discovery Year1960
Parity-

75Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

76Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
75.928827624 ± 0.0000021 Da
Mass Number76
G-Factor
-0.4725 ± 0.002
Half Life
30.6 ± 0.6 s
Spin2
Quadrupole Moment
0.33 ± 0.02
Discovery Year1961
Parity-

76Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

77Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
76.929154299 ± 0.0000026 Da
Mass Number77
G-Factor
1.3453333333333 ± 0.002
Half Life
13.2 ± 0.2 s
Spin3/2
Quadrupole Moment
-0.208 ± 0.013
Discovery Year1968
Parity-

77Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

78Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
77.931610854 ± 0.000001127 Da
Mass Number78
G-Factor
-0.607 ± 0.0025
Half Life
5.09 ± 0.05 s
Spin2
Quadrupole Moment
0.33 ± 0.02
Discovery Year1972
Parity-

78Ga Decay Modes
Decay ModeIntensity
β (β decay)100%

79Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
78.932851582 ± 0.000001296 Da
Mass Number79
G-Factor
0.69733333333333 ± 0.002
Half Life
2.848 ± 0.003 s
Spin3/2
Quadrupole Moment
0.158 ± 0.01
Discovery Year1974
Parity-

79Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)0.089%

80Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
79.936420773 ± 0.000003103 Da
Mass Number80
G-Factor
0.006 ± 0.00066666666666667
Half Life
1.9 ± 0.1 s
Spin6
Quadrupole Moment
0.38 ± 0.02
Discovery Year1974
Parity-

80Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)0.86%

81Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
80.938133841 ± 0.000003503 Da
Mass Number81
G-Factor
0.6984 ± 0.002
Half Life
1.217 ± 0.005 s
Spin5/2
Quadrupole Moment
-0.048 ± 0.008
Discovery Year1976
Parity-

81Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)12.5%

82Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
81.943176531 ± 0.000002604 Da
Mass Number82
G-Factor
Half Life
600 ± 2 ms
Spin2
Quadrupole Moment
Discovery Year1976
Parity-

82Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)21.2%
2n (2-neutron emission)%

83Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
82.9471203 ± 0.000002804 Da
Mass Number83
G-Factor
Half Life
310 ± 0.7 ms
Spin5/2
Quadrupole Moment
Discovery Year1976
Parity-

83Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)85%
2n (2-neutron emission)%

84Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
83.952663 ± 0.000032 Da
Mass Number84
G-Factor
0
Half Life
97.6 ± 1.2 ms
Spin0
Quadrupole Moment
0
Discovery Year1991
Parity-

84Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)43%
2n (2-neutron emission)1.6%

85Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
84.957333 ± 0.00004 Da
Mass Number85
G-Factor
Half Life
95.3 ± 1 ms
Spin5/2
Quadrupole Moment
Discovery Year1997
Parity-

85Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)77%
2n (2-neutron emission)1.3%

86Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
85.963757 ± 0.000429 Da
Mass Number86
G-Factor
Half Life
49 ± 2 ms
Spin
Quadrupole Moment
Discovery Year1997
Parity

86Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)69%
2n (2-neutron emission)16.2%

87Ga

AbundanceRadioactive ☢️
Relative Atomic Mass
86.969007 ± 0.000537 Da
Mass Number87
G-Factor
Half Life
29 ± 4 ms
Spin5/2
Quadrupole Moment
Discovery Year2010
Parity-

87Ga Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)81%
2n (2-neutron emission)10.2%

88Ga

Abundance
Relative Atomic Mass
87.975963 ± 0.000537 Da
Mass Number88
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

88Ga Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%

History

In 1871, existence of gallium was first predicted by Russian chemist Dmitri Mendeleev and called the element eka-aluminum. Gallium was discovered spectroscopically by French chemist Paul Emile Lecoq de Boisbaudran in 1875 by its characteristic spectrum in an examination of a sphalerite sample. Later that year, Lecoq obtained the free metal by electrolysis of its hydroxide in potassium hydroxide solution. From the Latin word Gallia, France; also from Latin, gallus, a translation of Lecoq, a cock

DiscoverersPaul Émile Lecoq de Boisbaudran
Discovery LocationFrance
Discovery Year1875
Etymology (Name Origin)Latin: Gallia (France).
PronunciationGAL-i-em (English)
Gallium is considered to be non-toxic
Gallium has a strong tendency to supercool below its melting point / freezing point

Uses

Gallium wets glass or porcelain and forms a brilliant mirror when it is painted on glass. It is widely used in doping semiconductors and producing solid-state devices such as transistors. Low melting gallium alloys are used in some medical thermometers as non-toxic substitutes for mercury. Gallium arsenide is capable of converting electricity directly into coherent light. Used in semiconductor production. It us used in making LEDs (light-emitting diodes) and GaAs laser diodes.

Sources

Found throughout the crust in minerals like bauxite, germanite and coal.

Abundance
Abundance in Earth's crust
Abundance in Oceans
0.00003 mg/L
Abundance in Human Body
Abundance in Meteor
0.00076 %
Abundance in Sun
0.000004 %
Abundance in Universe
0.000001 %

Nuclear Screening Constants

1s0.6906
2p3.9092
2s8.401
3d15.9067
3p14.7964
3s14.0038
4p24.7784
4s23.9332