Niobium
Element 41 · Transition Metal
Niobium is a shiny, ductile metal that becomes a superconductor at very low temperatures, which makes niobium-titanium wire the standard material for the powerful magnets inside MRI scanners and particle accelerators. Even at room temperature it is valuable: tiny additions of niobium dramatically strengthen steel, so it is used in pipelines, car frames, and construction steels. Niobium is chemically twinned with tantalum — the two are so similar that they were once thought to be the same element, and its name nods to that pairing through Greek mythology.
Key facts
| Atomic number | 41 |
|---|---|
| Atomic weight | 92.906 |
| Category | Transition Metal |
| Group / Period | 5 / 5 |
| Block | d |
| Electron configuration | [Kr] 4d4 5s1 |
| Common oxidation states | +5, +3 |
| State at STP | Solid |
| Electronegativity | 1.6 |
| Atomic radius | 146 pm (empirical) |
| Density | 8.57 g/cm³ |
| Melting point | 2477 °C |
| Boiling point | 4744 °C |
Occurrence
Niobium is extracted mainly from the mineral pyrochlore, with Brazil producing the great majority of the world's supply. It also occurs in columbite, the mineral that gave niobium its alternate historical name, columbium.
Applications
Superconducting magnets in MRI scanners
High-strength low-alloy steels
Superconducting radio-frequency cavities
Hypoallergenic jewelry
Common compounds
- Niobium pentoxide
- Niobium-titanium alloy
- Ferroniobium
Niobium is named after Niobe, daughter of Tantalus in Greek myth — a deliberate nod to its chemical twin tantalum, which sits directly below it in the periodic table.
Data source: IUPAC standard atomic weights 2021; NIST physical property data