Samarium (Sm) – element 62
Samarium is a chemical element with the symbol Sm and atomic number 62. It is a lanthanide in group 3 (lanthanides), period 6 of the periodic table (f-block), and is a solid at room temperature.
Samarium (Sm) has atomic number 62, atomic mass 150.36 u and electron configuration [Xe] 4f6 6s2.
Samarium facts
| Symbol | Sm |
|---|---|
| Atomic number | 62 |
| Atomic mass | 150.36 u (g/mol) |
| Category | lanthanide |
| Group | group 3 (lanthanides) |
| Period | 6 |
| Block | f-block |
| Phase at 20 °C | Solid |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f6 |
| Noble-gas notation | [Xe] 4f6 6s2 |
| Electrons per shell | 2, 8, 18, 24, 8, 2 |
Bohr model and shells
Samarium has 62 electrons in 6 shells: 2, 8, 18, 24, 8, 2. Full configuration and noble-gas notation are in the table; work out any element or ion with the electron configuration calculator.
Physical and atomic properties
| Melting point | 1345 K (1071.8 °C) |
|---|---|
| Boiling point | 2173 K (1899.8 °C) |
| Density | 7.52 g/cm³ |
| Electronegativity (Pauling) | 1.17 |
| Electron affinity | 15.63 kJ/mol |
| Ionization energies | 544.5, 1070, 2260 kJ/mol (1st, 2nd, 3rd) |
| Molar heat capacity | 29.54 J/(mol·K) |
| Discovered by | Lecoq de Boisbaudran |
Use the atomic mass in the molar mass calculator for any formula containing Sm.
Position in the periodic table
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Frequently asked questions
What is the atomic mass of samarium?
The atomic mass of samarium is 150.36 u, so one mole of samarium atoms weighs 150.36 g.
What is the electron configuration of samarium?
Samarium has 62 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f⁶, or [Xe] 4f⁶ 6s² in noble-gas notation. Electrons per shell: 2, 8, 18, 24, 8, 2.
Is samarium a metal?
Yes. Samarium is a lanthanide.
Where is samarium on the periodic table?
Samarium is in group 3 (lanthanides), period 6, in the f-block.
Data: Periodic-Table-JSON (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.