Terbium (Tb)
Terbium (Tb) is element 65, a lanthanide. Atomic mass 158.925354, configuration [Xe] 4f⁹ 6s². Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 65 |
|---|---|
| Symbol | Tb |
| Standard atomic weight | 158.925354(7) |
| Category | Lanthanide |
| Period | 6 |
| State at room temperature | Solid |
| Electron configuration | [Xe] 4f⁹ 6s² |
| Valence electrons | 2 (Variable) |
| Common oxidation states | +3 |
| Common ions | No common ions |
| First ionization energy | 566 kJ/mol |
| Atomic radius | 175 pm |
| Density | 8.23 g/cm³ |
| Melting point | 1351°C |
| Boiling point | 3230°C |
| Specific heat | 0.182 J/(g·°C) |
Natural isotopes
- Tb-159: Stable
Common uses
- Green phosphors (fluorescent lamps)
- Terfenol-D (magnetostrictive alloy)
Where it matters
- Green Energy (Low-energy lighting phosphors)
Hazards
- Low toxicity
History
| Discovered | 1843 |
|---|---|
| Discovered by | Carl Gustaf Mosander |
| Name | From Ytterby, Sweden |