Cerium

Cerium (Ce)

Silvery metallic element, belongs to the lanthanoids. Four natural isotopes exist, and fifteen radioactive isotopes have been identified. Used in some rare-earth alloys. The oxidized form is used in the glass industry. Discovered by Martin .H. Klaproth in 1803.
Atomic Number58
Atomic Weight140.116
Mass Number140
Group
Period6
Blockf
Protons58 p+
Neutrons82 n0
Electrons58 e-
CE2k2g.jpg Animated Bohr Model of Ce (Cerium) Enhanced Bohr Model of Ce (Cerium) Bohr Model: Ce (Cerium) Orbital Diagram of Ce (Cerium)

Properties

Atomic Radius
185 pm
Molar Volume
Covalent Radius
163 pm
Metallic Radius
Ionic Radius
101 pm
Crystal Radius
115 pm
Van der Waals Radius
242 pm
Density
6.77 g/cm³
Energy
Proton Affinity
Electron Affinity
Ionization Energy
Heat of Vaporization
398 kJ/mol
Heat of Fusion
5.2 kJ/mol
Heat of Formation
420.1 kJ/mol
Electrons
Electron Shells2, 8, 18, 19, 9, 2
Valence Electrons4
Electron Configuration[Xe] 4f1 5d1 6s2
Oxidation States2, 3, 4
Electronegativity
1.12
Electrophilicity
0.9792877807552266 eV/particle
Phases
PhaseSolid
Gas Phase
Boiling Point
3,716.15 K
Melting Point
1,072.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Silver
Appearancesilvery white
Refractive Index
Thermodynamic Properties
Thermal Conductivity
11.3 W/(m K)
Thermal Expansion
0.0000063 1/K
Molar Heat Capacity
26.94 J/(mol K)
Specific Heat Capacity
0.192 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
1.4 MS/m
Electrical Resistivity
0.00000075 m Ω
Superconducting Point
0.022 K
Magnetism
Typeparamagnetic
Magnetic Susceptibility (Mass)
0.00000022 m³/Kg
Magnetic Susceptibility (Molar)
0.000000030826 m³/mol
Magnetic Susceptibility (Volume)
0.0014716
Magnetic Ordering
Curie Point
Neel Point
12.5 K
Structure
Crystal StructureSimple Hexagonal (FCC)
Lattice Constant
5.16 Å
Lattice Anglesπ/2, π/2, 2 π/3
Mechanical Properties
Hardness
2.5 MPa
Bulk Modulus
22 GPa
Shear Modulus
14 GPa
Young Modulus
34 GPa
Poisson Ratio
0.24
Speed of Sound
2,100 m/s
Classification
CategoryLanthanides, Lanthanides
CAS Group
IUPAC Group
Glawe Number31
Mendeleev Number15
Pettifor Number32
Geochemical Classrare earth & related
Goldschmidt Classlitophile
Other
Gas Basicity
Dipole Polarizability
205 ± 20 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
0.6
Neutron Mass Absorption
0.00021
Quantum Numbers1G4
Space Group194 (P63/mmc)

Isotopes of Cerium

Stable Isotopes4
Unstable Isotopes37
Radioactive Isotopes36

119Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
118.952957 ± 0.000537 Da
Mass Number119
G-Factor
Half Life
Spin5/2
Quadrupole Moment
Discovery Year
Parity+

119Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

120Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
119.946613 ± 0.000537 Da
Mass Number120
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year
Parity+

120Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

121Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
120.943435 ± 0.00043 Da
Mass Number121
G-Factor
Half Life
1.1 ± 0.1 s
Spin5/2
Quadrupole Moment
Discovery Year1997
Parity

121Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)1%

122Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
121.93787 ± 0.00043 Da
Mass Number122
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year2005
Parity+

122Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)%
β+ p (β+-delayed proton emission)%

123Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
122.93528 ± 0.00032 Da
Mass Number123
G-Factor
Half Life
3.8 ± 0.2 s
Spin5/2
Quadrupole Moment
Discovery Year1984
Parity

123Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)%

124Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
123.93031 ± 0.00032 Da
Mass Number124
G-Factor
0
Half Life
9.1 ± 1.2 s
Spin0
Quadrupole Moment
0
Discovery Year1978
Parity+

124Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

125Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
124.92844 ± 0.00021 Da
Mass Number125
G-Factor
Half Life
9.7 ± 0.3 s
Spin7/2
Quadrupole Moment
Discovery Year1978
Parity-

125Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
β+ p (β+-delayed proton emission)%

126Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
125.923971 ± 0.00003 Da
Mass Number126
G-Factor
0
Half Life
51 ± 0.3 s
Spin0
Quadrupole Moment
0
Discovery Year1978
Parity+

126Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

127Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
126.922727 ± 0.000031 Da
Mass Number127
G-Factor
Half Life
34 ± 2 s
Spin1/2
Quadrupole Moment
0
Discovery Year1978
Parity+

127Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

128Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
127.918911 ± 0.00003 Da
Mass Number128
G-Factor
0
Half Life
3.93 ± 0.02 m
Spin0
Quadrupole Moment
0
Discovery Year1968
Parity+

128Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

129Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
128.918102 ± 0.00003 Da
Mass Number129
G-Factor
Half Life
3.5 ± 0.3 m
Spin5/2
Quadrupole Moment
Discovery Year1977
Parity+

129Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

130Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
129.914736 ± 0.00003 Da
Mass Number130
G-Factor
0
Half Life
22.9 ± 0.5 m
Spin0
Quadrupole Moment
0
Discovery Year1965
Parity+

130Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

131Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
130.914429465 ± 0.000035214 Da
Mass Number131
G-Factor
Half Life
10.3 ± 0.3 m
Spin7/2
Quadrupole Moment
Discovery Year1966
Parity+

131Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

132Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
131.911466226 ± 0.000021907 Da
Mass Number132
G-Factor
0
Half Life
3.51 ± 0.11 h
Spin0
Quadrupole Moment
0
Discovery Year1960
Parity+

132Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

133Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
132.911520402 ± 0.000017557 Da
Mass Number133
G-Factor
Half Life
97 ± 4 m
Spin1/2
Quadrupole Moment
0
Discovery Year1951
Parity+

133Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

134Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
133.908928142 ± 0.000021886 Da
Mass Number134
G-Factor
0
Half Life
3.16 ± 0.04 d
Spin0
Quadrupole Moment
0
Discovery Year1951
Parity+

134Ce Decay Modes
Decay ModeIntensity
ϵ (electron capture)100%

135Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
134.909160662 ± 0.000011021 Da
Mass Number135
G-Factor
Half Life
17.7 ± 0.3 h
Spin1/2
Quadrupole Moment
0
Discovery Year1948
Parity+

135Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

136Ce

Abundance
0.186 ± 0.002
Relative Atomic Mass
135.907129256 ± 0.000000348 Da
Mass Number136
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1936
Parity+

136Ce Decay Modes
Decay ModeIntensity
+ (double β+ decay)%

137Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
136.907762416 ± 0.000000386 Da
Mass Number137
G-Factor
0.64 ± 0.026666666666667
Half Life
9 ± 0.3 h
Spin3/2
Quadrupole Moment
Discovery Year1948
Parity+

137Ce Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

138Ce

Abundance
0.251 ± 0.002
Relative Atomic Mass
137.90599418 ± 0.000000536 Da
Mass Number138
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1936
Parity+

138Ce Decay Modes
Decay ModeIntensity
+ (double β+ decay)%

139Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
138.906647029 ± 0.000002242 Da
Mass Number139
G-Factor
0.70666666666667 ± 0.026666666666667
Half Life
137.642 ± 0.02 d
Spin3/2
Quadrupole Moment
Discovery Year1948
Parity+

139Ce Decay Modes
Decay ModeIntensity
ϵ (electron capture)100%

140Ce

Abundance
88.449 ± 0.051
Relative Atomic Mass
139.905448433 ± 0.000001409 Da
Mass Number140
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1925
Parity+

141Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
140.908285991 ± 0.000001411 Da
Mass Number141
G-Factor
0.31142857142857 ± 0.011428571428571
Half Life
32.505 ± 0.01 d
Spin7/2
Quadrupole Moment
Discovery Year1948
Parity-

141Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

142Ce

Abundance
11.114 ± 0.051
Relative Atomic Mass
141.909250208 ± 0.000002623 Da
Mass Number142
G-Factor
0
Half Life
Spin0
Quadrupole Moment
0
Discovery Year1925
Parity+

142Ce Decay Modes
Decay ModeIntensity
α (α emission)%
(double β decay)%

143Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
142.912391953 ± 0.000002621 Da
Mass Number143
G-Factor
0.28666666666667 ± 0.0066666666666667
Half Life
33.039 ± 0.006 h
Spin3/2
Quadrupole Moment
Discovery Year1948
Parity-

143Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

144Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
143.913652763 ± 0.000003041 Da
Mass Number144
G-Factor
0
Half Life
284.886 ± 0.025 d
Spin0
Quadrupole Moment
0
Discovery Year1945
Parity+

144Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

145Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
144.917265113 ± 0.000036393 Da
Mass Number145
G-Factor
Half Life
3.01 ± 0.06 m
Spin5/2
Quadrupole Moment
Discovery Year1954
Parity-

145Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

146Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
145.918812294 ± 0.000015743 Da
Mass Number146
G-Factor
0
Half Life
13.49 ± 0.16 m
Spin0
Quadrupole Moment
0
Discovery Year1953
Parity+

146Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

147Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
146.9226899 ± 0.000009211 Da
Mass Number147
G-Factor
Half Life
56.4 ± 1 s
Spin5/2
Quadrupole Moment
Discovery Year1964
Parity-

147Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

148Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
147.924424186 ± 0.000012017 Da
Mass Number148
G-Factor
0
Half Life
56.8 ± 0.3 s
Spin0
Quadrupole Moment
0
Discovery Year1964
Parity+

148Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

149Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
148.9284269 ± 0.000011 Da
Mass Number149
G-Factor
Half Life
4.94 ± 0.04 s
Spin3/2
Quadrupole Moment
Discovery Year1974
Parity-

149Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

150Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
149.930384032 ± 0.000012556 Da
Mass Number150
G-Factor
0
Half Life
6.05 ± 0.07 s
Spin0
Quadrupole Moment
0
Discovery Year1970
Parity+

150Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

151Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
150.9342722 ± 0.000019 Da
Mass Number151
G-Factor
Half Life
1.76 ± 0.06 s
Spin3/2
Quadrupole Moment
Discovery Year1997
Parity-

151Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

152Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
151.936682 ± 0.000215 Da
Mass Number152
G-Factor
0
Half Life
1.42 ± 0.02 s
Spin0
Quadrupole Moment
0
Discovery Year1990
Parity+

152Ce Decay Modes
Decay ModeIntensity
β (β decay)100%

153Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
152.941052 ± 0.000215 Da
Mass Number153
G-Factor
Half Life
865 ± 25 ms
Spin3/2
Quadrupole Moment
Discovery Year1994
Parity-

153Ce Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

154Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
153.94394 ± 0.000215 Da
Mass Number154
G-Factor
0
Half Life
722 ± 14 ms
Spin0
Quadrupole Moment
0
Discovery Year1994
Parity+

154Ce Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

155Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
154.948706 ± 0.000322 Da
Mass Number155
G-Factor
Half Life
313 ± 7 ms
Spin5/2
Quadrupole Moment
Discovery Year1994
Parity-

155Ce Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

156Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
155.951884 ± 0.000322 Da
Mass Number156
G-Factor
0
Half Life
233 ± 9 ms
Spin0
Quadrupole Moment
0
Discovery Year2017
Parity+

156Ce Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

157Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
156.957133 ± 0.000429 Da
Mass Number157
G-Factor
Half Life
175 ± 41 ms
Spin7/2
Quadrupole Moment
Discovery Year2017
Parity+

157Ce Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

158Ce

AbundanceRadioactive ☢️
Relative Atomic Mass
157.960773 ± 0.000429 Da
Mass Number158
G-Factor
0
Half Life
99 ± 93 ms
Spin0
Quadrupole Moment
0
Discovery Year2016
Parity+

158Ce Decay Modes
Decay ModeIntensity
β (β decay)100%
β n (β-delayed neutron emission)%

159Ce

Abundance
Relative Atomic Mass
158.966355 ± 0.000537 Da
Mass Number159
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year
Parity-

159Ce Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%

History

Jöns Jakob Berzelius and Wilhelm Hisinger discovered the element in ceria in 1803 in Sweden. Klaproth discovered it simultaneously and independently in some tantalum samples in Germany. Carl Gustaf Mosander, who worked closely with Berzelius, prepared metallic cerium in 1825. Cerium was named for the asteroid Ceres

DiscoverersW. von Hisinger, J. Berzelius, M. Klaproth
Discovery LocationSweden/Germany
Discovery Year1803
Etymology (Name Origin)Named after the asteroid, Ceres, discovered two years before the element.
PronunciationSER-i-em (English)
Cerium is considered to be moderately toxic
Seawater contains 1.5 parts per trillion of cerium

Uses

Cerium is used in carbon-arc lighting, especially in the motion picture industry. Cerium oxide is an important component of glass polishing powders and phosphors used in screens and fluorescent lamps. Cerium compounds are also used in the manufacture of glass, both as a component and as a decolorizer. Its oxides are used in the optics and glass-making industries. Its salts are used in the photography and textile industry. Used in high-intensity carbon lamps and as alloying agents in special metals.

Sources

Most abundant rare earth metal. Found in many minerals like monazite sand [Ce(PO4)].

Abundance
Abundance in Earth's crust
66.5 mg/kg
Abundance in Oceans
0.0000012 mg/L
Abundance in Human Body
Abundance in Meteor
0.000075 %
Abundance in Sun
0.0000004 %
Abundance in Universe
0.000001 %

Nuclear Screening Constants

1s1.1519
2p4.2176
2s15.26
3d13.9147
3p19.0405
3s19.3408
4d32.3392
4f56.324
4p29.3936
4s28.32
5p41.0345
5s39.0865
6s47.2036