Samarium (Sm)

Samarium is the 62nd element in the periodic table and has a symbol of Sm and atomic number of 62. It has an atomic weight of 150.36 and a mass number of 152. Samarium has sixty-two protons and ninety neutrons in its nucleus, and sixty-two electrons in six shells. It is located in group zero, period six and block f of the periodic table. Soft silvery metallic element, belongs to the lanthanoids. Seven natural isotopes, Sm-147 is the only radioisotope, and has a half-life of 2.5*10^11 years. Used for making special alloys needed in the production of nuclear reactors. Also used as a neutron absorber. Small quantities of samarium oxide is used in special optical glasses. The largest use of the element is its ferromagnetic alloy which produces permanent magnets that are five times stronger than magnets produced by any other material. Discovered by Francois Lecoq de Boisbaudran in 1879.

Atomic Number	62
Atomic Weight	150.36
Mass Number	152

Group
Period	6
Block	f

Protons	62 p⁺
Neutrons	90 n⁰
Electrons	62 e^-

Properties

Physical Properties
Atomic Radius	185 pm 280 pm
Molar Volume	19.9 cm³/mol
Covalent Radius	172 pm 134 pm 198 pm
Metallic Radius
Ionic Radius	122 pm 127 pm 132 pm 95.8 pm 102 pm 107.9 pm 113.2 pm 124 pm
Crystal Radius	136 pm 141 pm 146 pm 109.8 pm 116 pm 121.9 pm 127.2 pm 138 pm
Van der Waals Radius	236 pm 271 pm 352 pm
Density	7.52 g/cm³ 7,160 kg/m³
Energy
Proton Affinity
Electron Affinity
Ionization Energy	5.64371 eV/particle 11.07 eV/particle 23.4 eV/particle 41.4 eV/particle 62.66 eV/particle 90 eV/particle 103 eV/particle 118 eV/particle 141 eV/particle 158 eV/particle 179 eV/particle 208 eV/particle 237 eV/particle 257 eV/particle 276 eV/particle 306.5 eV/particle 474 eV/particle 506 eV/particle 543 eV/particle 581 eV/particle 617 eV/particle 658 eV/particle 702 eV/particle 742 eV/particle 782 eV/particle 822 eV/particle 976 eV/particle 1,016 eV/particle 1,060 eV/particle 1,103 eV/particle 1,180 eV/particle 1,226 eV/particle 1,332 eV/particle 1,381.6 eV/particle 2,371 eV/particle 2,466 eV/particle 2,569 eV/particle 2,676 eV/particle 2,782 eV/particle 2,887 eV/particle 3,028 eV/particle 3,137 eV/particle 3,253 eV/particle 3,363 eV/particle 3,669 eV/particle 3,766 eV/particle 3,873 eV/particle 3,971 eV/particle 4,227 eV/particle 4,337 eV/particle 4,548 eV/particle 4,655 eV/particle 10,494 eV/particle 10,762 eV/particle 11,060 eV/particle 11,337 eV/particle 12,264 eV/particle 12,588 eV/particle 12,992 eV/particle 13,262.85 eV/particle 53,986.11 eV/particle 55,214.23 eV/particle

Heat of Vaporization	165 kJ/mol
Heat of Fusion	8.9 kJ/mol
Heat of Formation	206.7 kJ/mol
Electrons
Electron Shells	2, 8, 18, 24, 8, 2

Valence Electrons	2

Electron Configuration	[Xe] 4f⁶ 6s²

Oxidation States	0, 1, 2, 3
Electronegativity	0.185468 1.17
Electrophilicity
Phases
Phase	Solid
Gas Phase
Boiling Point	2,067.15 K
Melting Point	1,345.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Samarium is a Silver. Sm has a CPK of #ff1493, Jmol of #8fffc7, and MOLCAS GV of #8fffc7. The Appearance of Element 62 is silvery white.
Color	Silver #ff1493 #8fffc7 #8fffc7
Appearance	silvery white
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion	0.0000127 1/K
Molar Heat Capacity	29.54 J/(mol K)
Specific Heat Capacity	0.197 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Conductor
Electrical Conductivity	1.1 MS/m
Electrical Resistivity	0.00000094 m Ω
Superconducting Point
Magnetism
Type	paramagnetic
Magnetic Susceptibility (Mass)	0.000000111 m³/Kg
Magnetic Susceptibility (Molar)	0.00000001669 m³/mol
Magnetic Susceptibility (Volume)	0.00081618
Magnetic Ordering
Curie Point
Neel Point	106 K
Structure
The Crystal Structure of Samarium is RHL. The lattice constant of Sm is 9 Å. The lattice angles of Element 62 are π/2, π/2, 2 π/3.
Crystal Structure	Simple Trigonal (RHL)
Lattice Constant	9 Å
Lattice Angles	π/2, π/2, 2 π/3
Mechanical Properties
Samarium has a Brinell of 441 MPa, and Vickers of 412 MPa. The Bulk Modulus of Sm is 38 GPa. The Shear Modulus of Element 62 is 20 GPa. The Young Modulus of Samarium (Sm) is 50 GPa. The Poisson Ratio of Samarium is 0.27. The Speed of Sound of Sm is 2130 m/s.
Hardness	441 MPa 412 MPa
Bulk Modulus	38 GPa
Shear Modulus	20 GPa
Young Modulus	50 GPa
Poisson Ratio	0.27
Speed of Sound	2,130 m/s
Classification
The Glawe Number of Samarium is 27. The Mendeleev Number of Sm is 23. The Pettifor Number of Element 62 is 28. The Geochemical Class of Samarium (Sm) is rare earth & related. The Goldschmidt Class of Samarium is litophile.
Category	Lanthanides, Lanthanides
CAS Group
IUPAC Group
Glawe Number	27
Mendeleev Number	23
Pettifor Number	28
Geochemical Class	rare earth & related
Goldschmidt Class	litophile
Other
The Dipole Polarizability of Samarium is 192 plus or minus 20 a₀. Sm has a C6 Dispersion Coefficient (GB) of 3130 a₀. The Allotropes of Element 62 is . The Neutron Cross Section of Samarium (Sm) is 5900. The Neutron Mass Absorption of Samarium is 4.7. The Quantum Numbers of Sm is 7F0. The Space Group of Element 62 is 166 (R_3m).
Gas Basicity
Dipole Polarizability	192 ± 20 a₀
C6 Dispersion Coefficient	3,130 a₀
Allotropes
Neutron Cross Section	5,900
Neutron Mass Absorption	4.7
Quantum Numbers	7F0
Space Group	166 (R_3m)

Isotopes of Samarium

Stable Isotopes	7
Unstable Isotopes	34
Radioactive Isotopes	36

¹²⁸Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	127.957971 ± 0.000537 Da
Mass Number	128
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year
Parity	+

¹²⁸Sm Decay Modes

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

¹²⁹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	128.954557 ± 0.000537 Da
Mass Number	129
G-Factor
Half Life	550 ± 100 ms
Spin	1/2
Quadrupole Moment	0
Discovery Year	1999
Parity	+

¹²⁹Sm Decay Modes

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

¹³⁰Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	129.948792 ± 0.000429 Da
Mass Number	130
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1999
Parity	+

¹³⁰Sm Decay Modes

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

¹³¹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	130.946022 ± 0.000429 Da
Mass Number	131
G-Factor
Half Life	1.2 ± 0.2 s
Spin	5/2
Quadrupole Moment
Discovery Year	1986
Parity	+

¹³¹Sm Decay Modes

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

¹³²Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	131.940805 ± 0.000322 Da
Mass Number	132
G-Factor	0
Half Life	4 ± 0.3 s
Spin	0
Quadrupole Moment	0
Discovery Year	1989
Parity	+

¹³²Sm Decay Modes

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

¹³³Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	132.93856 ± 0.00032 Da
Mass Number	133
G-Factor
Half Life	2.89 ± 0.16 s
Spin	5/2
Quadrupole Moment
Discovery Year	1977
Parity	+

¹³³Sm Decay Modes

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

¹³⁴Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	133.93411 ± 0.00021 Da
Mass Number	134
G-Factor	0
Half Life	9.5 ± 0.8 s
Spin	0
Quadrupole Moment	0
Discovery Year	1977
Parity	+

¹³⁴Sm Decay Modes

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

¹³⁵Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	134.93252 ± 0.000166 Da
Mass Number	135
G-Factor
Half Life	10.3 ± 0.5 s
Spin	7/2
Quadrupole Moment
Discovery Year	1977
Parity	+

¹³⁵Sm Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ p (β⁺-delayed proton emission)	0.02%

¹³⁶Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	135.928275553 ± 0.000013416 Da
Mass Number	136
G-Factor	0
Half Life	47 ± 2 s
Spin	0
Quadrupole Moment	0
Discovery Year	1982
Parity	+

¹³⁶Sm Decay Modes

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

¹³⁷Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	136.927007959 ± 0.000030718 Da
Mass Number	137
G-Factor
Half Life	45 ± 1 s
Spin	9/2
Quadrupole Moment
Discovery Year	1986
Parity	-

¹³⁷Sm Decay Modes

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

¹³⁸Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	137.923243988 ± 0.000012686 Da
Mass Number	138
G-Factor	0
Half Life	3.1 ± 0.2 m
Spin	0
Quadrupole Moment	0
Discovery Year	1982
Parity	+

¹³⁸Sm Decay Modes

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

¹³⁹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	138.922296631 ± 0.000011684 Da
Mass Number	139
G-Factor	-1.06 ± 0.04
Half Life	2.57 ± 0.1 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1971
Parity	+

¹³⁹Sm Decay Modes

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

¹⁴⁰Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	139.918994714 ± 0.000013416 Da
Mass Number	140
G-Factor	0
Half Life	14.82 ± 0.12 m
Spin	0
Quadrupole Moment	0
Discovery Year	1967
Parity	+

¹⁴⁰Sm Decay Modes

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

¹⁴¹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	140.918481545 ± 0.000009162 Da
Mass Number	141
G-Factor	-1.48 ± 0.04
Half Life	10.2 ± 0.2 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1967
Parity	+

¹⁴¹Sm Decay Modes

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

¹⁴²Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	141.915209415 ± 0.000002002 Da
Mass Number	142
G-Factor	0
Half Life	72.49 ± 0.05 m
Spin	0
Quadrupole Moment	0
Discovery Year	1959
Parity	+

¹⁴²Sm Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
e⁺ (positron emission)	5%

¹⁴³Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	142.914634848 ± 0.000002951 Da
Mass Number	143
G-Factor	0.67333333333333 ± 0.013333333333333
Half Life	8.75 ± 0.06 m
Spin	3/2
Quadrupole Moment	0.4 ± 0.2
Discovery Year	1956
Parity	+

¹⁴³Sm Decay Modes

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
e⁺ (positron emission)	40%
ϵ (electron capture)	60%

¹⁴⁴Sm

Abundance	3.08 ± 0.04
Relative Atomic Mass	143.912006285 ± 0.000001566 Da
Mass Number	144
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1933
Parity	+

¹⁴⁴Sm Decay Modes

Decay Mode	Intensity
2β⁺ (double β⁺ decay)	%

¹⁴⁵Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	144.913417157 ± 0.000001594 Da
Mass Number	145
G-Factor	-0.32 ± 0.0031428571428571
Half Life	340 ± 3 d
Spin	7/2
Quadrupole Moment	-0.6 ± 0.07
Discovery Year	1947
Parity	-

¹⁴⁵Sm Decay Modes

Decay Mode	Intensity
ϵ (electron capture)	100%

¹⁴⁶Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	145.913046835 ± 0.000003269 Da
Mass Number	146
G-Factor	0
Half Life	68 ± 7 My
Spin	0
Quadrupole Moment	0
Discovery Year	1953
Parity	+

¹⁴⁶Sm Decay Modes

Decay Mode	Intensity
α (α emission)	100%

¹⁴⁷Sm

Abundance	Radioactive ☢️ 15 ± 0.14
Relative Atomic Mass	146.914904401 ± 0.000001354 Da
Mass Number	147
G-Factor	-0.23114285714286 ± 0.0004
Half Life	106.6 ± 0.5 Gy
Spin	7/2
Quadrupole Moment	-0.26 ± 0.03
Discovery Year	1933
Parity	-

¹⁴⁷Sm Decay Modes

Decay Mode	Intensity
α (α emission)	100%

¹⁴⁸Sm

Abundance	Radioactive ☢️ 11.25 ± 0.09
Relative Atomic Mass	147.914829233 ± 0.000001337 Da
Mass Number	148
G-Factor	0
Half Life	6.3 ± 1.3 Py
Spin	0
Quadrupole Moment	0
Discovery Year	1933
Parity	+

¹⁴⁸Sm Decay Modes

Decay Mode	Intensity
α (α emission)	100%

¹⁴⁹Sm

Abundance	13.82 ± 0.1
Relative Atomic Mass	148.917191211 ± 0.000001241 Da
Mass Number	149
G-Factor	-0.19077142857143 ± 0.00031428571428571
Half Life
Spin	7/2
Quadrupole Moment	0.075 ± 0.008
Discovery Year	1933
Parity	-

¹⁴⁹Sm Decay Modes

Decay Mode	Intensity
α (α emission)	%

¹⁵⁰Sm

Abundance	7.37 ± 0.09
Relative Atomic Mass	149.917281993 ± 0.000001193 Da
Mass Number	150
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1934
Parity	+

¹⁵¹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	150.919938859 ± 0.000001191 Da
Mass Number	151
G-Factor	-0.1442 ± 0.00024
Half Life	94.6 ± 0.6 y
Spin	5/2
Quadrupole Moment	0.71 ± 0.07
Discovery Year	1947
Parity	-

¹⁵¹Sm Decay Modes

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

¹⁵²Sm

Abundance	26.74 ± 0.09
Relative Atomic Mass	151.919738646 ± 0.00000109 Da
Mass Number	152
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1933
Parity	+

¹⁵³Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	152.922103576 ± 0.0000011 Da
Mass Number	153
G-Factor	-0.014 ± 0.002
Half Life	46.2846 ± 0.0023 h
Spin	3/2
Quadrupole Moment	1.3 ± 0.12
Discovery Year	1938
Parity	+

¹⁵³Sm Decay Modes

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

¹⁵⁴Sm

Abundance	22.74 ± 0.14
Relative Atomic Mass	153.922215756 ± 0.0000014 Da
Mass Number	154
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1933
Parity	+

¹⁵⁴Sm Decay Modes

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

¹⁵⁵Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	154.924646645 ± 0.000001429 Da
Mass Number	155
G-Factor
Half Life	22.18 ± 0.06 m
Spin	3/2
Quadrupole Moment	1.13 ± 0.13
Discovery Year	1951
Parity	-

¹⁵⁵Sm Decay Modes

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

¹⁵⁶Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	155.925538191 ± 0.000009148 Da
Mass Number	156
G-Factor	0
Half Life	9.4 ± 0.2 h
Spin	0
Quadrupole Moment	0
Discovery Year	1951
Parity	+

¹⁵⁶Sm Decay Modes

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

¹⁵⁷Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	156.928418598 ± 0.000004759 Da
Mass Number	157
G-Factor
Half Life	8.03 ± 0.07 m
Spin	3/2
Quadrupole Moment
Discovery Year	1973
Parity	-

¹⁵⁷Sm Decay Modes

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

¹⁵⁸Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	157.929949262 ± 0.000005133 Da
Mass Number	158
G-Factor	0
Half Life	5.3 ± 0.03 m
Spin	0
Quadrupole Moment	0
Discovery Year	1970
Parity	+

¹⁵⁸Sm Decay Modes

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

¹⁵⁹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	158.93321713 ± 0.00000637 Da
Mass Number	159
G-Factor
Half Life	11.37 ± 0.15 s
Spin	5/2
Quadrupole Moment
Discovery Year	1986
Parity	-

¹⁵⁹Sm Decay Modes

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

¹⁶⁰Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	159.935337032 ± 0.0000021 Da
Mass Number	160
G-Factor	0
Half Life	9.6 ± 0.3 s
Spin	0
Quadrupole Moment	0
Discovery Year	1986
Parity	+

¹⁶⁰Sm Decay Modes

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

¹⁶¹Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	160.939160062 ± 0.000007318 Da
Mass Number	161
G-Factor
Half Life	4.8 ± 0.4 s
Spin	7/2
Quadrupole Moment
Discovery Year	1998
Parity	+

¹⁶¹Sm Decay Modes

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

¹⁶²Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	161.941621687 ± 0.000003782 Da
Mass Number	162
G-Factor	0
Half Life	2.7 ± 0.3 s
Spin	0
Quadrupole Moment	0
Discovery Year	2005
Parity	+

¹⁶²Sm Decay Modes

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

¹⁶³Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	162.945679085 ± 0.0000079 Da
Mass Number	163
G-Factor
Half Life	1.3 ± 0.5 s
Spin	1/2
Quadrupole Moment	0
Discovery Year	2012
Parity	-

¹⁶³Sm Decay Modes

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

¹⁶⁴Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	163.948550061 ± 0.0000044 Da
Mass Number	164
G-Factor	0
Half Life	1.43 ± 0.24 s
Spin	0
Quadrupole Moment	0
Discovery Year	2012
Parity	+

¹⁶⁴Sm Decay Modes

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

¹⁶⁵Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	164.95329 ± 0.000429 Da
Mass Number	165
G-Factor
Half Life	980 ± 210 ms
Spin	5/2
Quadrupole Moment
Discovery Year	2012
Parity	-

¹⁶⁵Sm Decay Modes

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

¹⁶⁶Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	165.956575 ± 0.000429 Da
Mass Number	166
G-Factor	0
Half Life	800 ± 630 ms
Spin	0
Quadrupole Moment	0
Discovery Year	2017
Parity	+

¹⁶⁶Sm Decay Modes

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

¹⁶⁷Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	166.962072 ± 0.000537 Da
Mass Number	167
G-Factor
Half Life
Spin	7/2
Quadrupole Moment
Discovery Year	2018
Parity	-

¹⁶⁷Sm Decay Modes

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

¹⁶⁸Sm

Abundance	Radioactive ☢️
Relative Atomic Mass	167.966033 ± 0.000322 Da
Mass Number	168
G-Factor	0
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	2018
Parity	+

¹⁶⁸Sm Decay Modes

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

History

In 1853, Jean Charles Galissard de Marignac discovered samarium when he found lines in mineral spectra. Paul Émile Lecoq de Boisbaudran isolated a samarium salt in Paris in 1879 from the mineral samarskite and identified a new element in it via sharp optical absorption lines. The pure element was produced only in 1901 by Eugène-Anatole Demarçay. From samarskite, a mineral named after Russian mine official, Col. Samarski

Discoverers	Paul Émile Lecoq de Boisbaudran
Discovery Location	France
Discovery Year	1879
Etymology (Name Origin)	Named after the mineral samarskite.
Pronunciation	seh-MER-i-em (English)

Samarium is considered to be moderately toxic

Samarium metal can be produced by reducing the oxide with lanthanum

Uses

Samarium's main use is in samarium-cobalt alloy magnets for headphones, small motors and pickups for some electric guitars. Radioactive samarium-153 is used to kill cancer cells in the treatment of lung cancer, prostate cancer, breast cancer and osteosarcoma. Samarium and its compounds are also used as catalyst and chemical reagent. It is used in the electronics and ceramics industries. It is easily magnetized and very difficult to demagnetize. This suggests important future applications in solid-state and superconductor technologies.

Sources

Found with other rare earths in monazite sand. The sand is often 50% rare earths by weight and 2.8% samarium.

Abundance
Abundance in Earth's crust	7.05 mg/kg
Abundance in Oceans	0.00000045 mg/L
Abundance in Human Body
Abundance in Meteor	0.000017 %
Abundance in Sun	0.0000001 %
Abundance in Universe	0.0000005 %

Nuclear Screening Constants

1	s	1.2217
2	p	4.269
2	s	16.2652
3	d	13.7711
3	p	19.5815
3	s	19.9736
4	d	33.7604
4	f	38.4684
4	p	30.912
4	s	29.7076
5	p	45.719
5	s	43.751
6	s	53.9882

Samarium on ChemicalAid

Australian Educational Vocabulary ID	scot/3571
BNCF Thesaurus ID	38281
CAB ID	258535
CAS Registry Number	7440-19-9
ChEBI ID	33374
ChemSpider ID	22391
DSSTOX compound identifier	DTXCID6047652
DSSTox substance ID	DTXSID4064688
Den Store Danske ID	samarium
DrugBank ID	12403
ECHA Substance Infocard ID	100.028.298
Elhuyar ZTH ID	030419
Encyclopedia of China ID (Second Edition)	228324
Encyclopædia Britannica Online ID	science/samarium
Encyclopædia Universalis ID	samarium
Freebase ID	/m/025sf93
GND ID	4179010-8
Gran Enciclopèdia Catalana ID	0140967
Great Russian Encyclopedia Online ID	3530040
HSDB ID	7863
InChI	InChI=1S/Sm
InChIKey	KZUNJOHGWZRPMI-UHFFFAOYSA-N
KBpedia ID	Samarium
Library of Congress authority ID	sh85117001
MeSH descriptor ID	D012493
NKCR AUT ID	ph174621
Namuwiki ID	사마륨
National Library of Israel J9U ID	987007553579605171
OmegaWiki Defined Meaning	356071
OpenAlex ID	C536819264
Probes And Drugs ID	PD058083
PubChem CID	23951
Quora topic ID	Samarium
RxNorm ID	9549
Römpp online ID	RD-19-00275
Store norske leksikon ID	samarium
Treccani ID	samario
UNII	42OD65L39F
USGS Thesaurus ID	1566
WordNet 3.1 Synset ID	14677775-n

Samarium (Sm)

Properties

Isotopes of Samarium

128Sm

128Sm Decay Modes

129Sm

129Sm Decay Modes

130Sm

130Sm Decay Modes

131Sm

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132Sm

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133Sm

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134Sm

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135Sm

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136Sm

136Sm Decay Modes

137Sm

137Sm Decay Modes

138Sm

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139Sm

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140Sm

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141Sm

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142Sm

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143Sm

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144Sm

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145Sm

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146Sm

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147Sm

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148Sm

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149Sm

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150Sm

151Sm

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152Sm

153Sm

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154Sm

154Sm Decay Modes

155Sm

155Sm Decay Modes

156Sm

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157Sm

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158Sm

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159Sm

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160Sm

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161Sm

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162Sm

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163Sm

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164Sm

164Sm Decay Modes

165Sm

165Sm Decay Modes

166Sm

166Sm Decay Modes

167Sm