Niobium(V) bromide explained

Niobium(V) bromide is the inorganic compound with the formula Nb₂Br₁₀. Its name comes from the compound's empirical formula, NbBr₅.^[1] It is a diamagnetic, orange solid that hydrolyses readily. The compound adopts an edge-shared bioctahedral structure, which means that two NbBr₅ units are joined by a pair of bromide bridges. There is no bond between the Nb centres.^[2] Niobium(V) chloride, niobium(V) iodide, tantalum(V) chloride, tantalum(V) bromide, and tantalum(V) iodide all share this structural motif.

Synthesis

Niobium(V) bromide can be prepared by the reaction of bromine with niobium metal at 230-250 °C in a tube furnace. It can also be produced from the more accessible oxide by metathesis using aluminium tribromide:^[3]

Nb₂O₅ + 3.3AlBr₃ → 2NbBr₅ + 3.3Al₂O₃ A challenge with the latter method is the occurrence of NbOBr₃ as an impurity.

References

Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford: Butterworth-Heinemann. .
10.1515/znb-1990-0706. Synthesis and Crystal Structure of Ordered, Orthorhombic α-NbBr₅. 1990. Hönle. Wolfgang. Furuseth. Sigrid. Schnering. Hans Georg von. Zeitschrift für Naturforschung B. 45. 7. 952–956. 98293250. free.
Book: G. Brauer. Niobium(V) and Tantalum(V) Bromides. Handbook of Preparative Inorganic Chemistry, 2nd Ed. . G. Brauer. Academic Press. 1963. NY, NY. 1. 1311.

External links

Web Elements