62150.36SmSamarium
Samarium (Sm) — element 62lanthanide · period 6
Samarium is a chemical element with the symbol Sm and atomic number 62. It is a lanthanide in period 6 of the periodic table (the f-block), with a standard atomic mass of 150.36 u. At room temperature (25 °C) samarium is a solid.
💡 Known for: Samarium–cobalt magnets keep their strength at high temperatures; samarium-153 is used to relieve bone-cancer pain.
# Samarium properties
| Symbol | Sm |
|---|---|
| Atomic number | 62 |
| Atomic mass | 150.36 u |
| Category | lanthanide |
| Group | — (f-block, no group number) |
| Period | 6 |
| Block | f-block |
| Electron configuration | [Xe] 4f⁶ 6s² |
| Full configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f⁶ 5s² 5p⁶ 6s² |
| Electrons per shell | 2, 8, 18, 24, 8, 2 |
| Protons / electrons | 62 / 62 |
| State at 25 °C | solid |
| Melting point | 1345 K (1071.8 °C, 1961.3 °F) |
| Boiling point | 2067 K (1793.8 °C, 3260.9 °F) |
| Density | 7.52 g/cm³ |
| Electronegativity (Pauling) | 1.17 |
| First ionization energy | 5.644 eV |
| Atomic radius | 238 pm |
| Discovered | 1879 |
# Electron configuration of samarium
The electron configuration of samarium is [Xe] 4f⁶ 6s², written out in full as 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f⁶ 5s² 5p⁶ 6s². Its 62 electrons fill 6 shells as 2, 8, 18, 24, 8, 2, so the outermost shell holds 2 electrons.
# Related elements
PmPromethiumprevious elementEuEuropiumnext elementLaLanthanumlanthanideCeCeriumlanthanidePrPraseodymiumlanthanideNdNeodymiumlanthanideGdGadoliniumlanthanideTbTerbiumlanthanideDyDysprosiumlanthanideHoHolmiumlanthanide
# Samarium FAQ
What is the atomic number of samarium?
The atomic number of samarium is 62: every samarium atom has 62 protons in its nucleus. Its symbol is Sm.
What is the atomic mass of samarium?
The standard atomic mass of samarium is 150.36 u.
What is the electron configuration of samarium?
Samarium's electron configuration is [Xe] 4f⁶ 6s² (1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f⁶ 5s² 5p⁶ 6s²), with 2, 8, 18, 24, 8, 2 electrons per shell.
Is samarium a metal?
Yes. Samarium is a lanthanide, one of the metals.
What is the melting point of samarium?
Samarium melts at 1345 K (1071.8 °C, 1961.3 °F) and boils at 2067 K (1793.8 °C, 3260.9 °F).
What is samarium used for / known for?
Samarium–cobalt magnets keep their strength at high temperatures; samarium-153 is used to relieve bone-cancer pain.