Samarium
62
Sm
Group
n/a
Period
6
Block
f
Protons
Electrons
Neutrons
62
62
88
General Properties
Atomic Number
62
Atomic Weight
150.36
Mass Number
150
Category
Lanthanides
Color
Silver
Radioactive
No
From samarskite, a mineral named after Russian mine official, Col. Samarski
Crystal Structure
Simple Trigonal
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.
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.
Electrons per shell
2, 8, 18, 24, 8, 2
Electron Configuration
[Xe] 4f6 6s2
Samarium metal can be produced by reducing the oxide with lanthanum
Physical Properties
Phase
Solid
Density
7.52 g/cm3
Melting Point
1345.15 K | 1072 °C | 1961.6 °F
Boiling Point
2067.15 K | 1794 °C | 3261.2 °F
Heat of Fusion
8.6 kJ/mol
Heat of Vaporization
175 kJ/mol
Specific Heat Capacity
0.197 J/g·K
Abundance in Earth's crust
0.0006%
Abundance in Universe
5×10-7%
CAS Number
7440-19-9
PubChem CID Number
23951
Atomic Properties
Atomic Radius
180 pm
Covalent Radius
198 pm
Electronegativity
1.17 (Pauling scale)
Ionization Potential
5.6437 eV
Atomic Volume
20.0 cm3/mol
Thermal Conductivity
0.133 W/cm·K
Oxidation States
2, 3
Applications
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.
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.
Samarium is considered to be moderately toxic
Isotopes
Stable Isotopes
144Sm, 149Sm, 150Sm, 152Sm, 154SmUnstable Isotopes
128Sm, 129Sm, 130Sm, 131Sm, 132Sm, 133Sm, 134Sm, 135Sm, 136Sm, 137Sm, 138Sm, 139Sm, 140Sm, 141Sm, 142Sm, 143Sm, 145Sm, 146Sm, 147Sm, 148Sm, 151Sm, 153Sm, 155Sm, 156Sm, 157Sm, 158Sm, 159Sm, 160Sm, 161Sm, 162Sm, 163Sm, 164Sm, 165Sm