Niobium(V) bromide
Names
Other names
niobium pentabromide
Identifiers
ChemSpider
ECHA InfoCard
100.033.420
EC Number
InChI=1S/5BrH.Nb/h5*1H;/q;;;;;+5/p-5
Y Key: DSYRJFDOOSKABR-UHFFFAOYSA-I
Y InChI=1/5BrH.Nb/h5*1H;/q;;;;;+5/p-5
Key: DSYRJFDOOSKABR-AACRGIKGAJ
[Br-].[Br-].[Br-].[Br-].[Br-].[Nb+5]
Properties
NbBr5
Molar mass
492.430 g/mol
Appearance
wine red to black crystals
Density
4.417 g/cm3
Melting point
254 °C (489 °F; 527 K)
Boiling point
364 °C (687 °F; 637 K)
hydrolysis
Structure
orthorhombic
Hazards
GHS labelling :[ 1]
Danger
H302 , H312 , H314 , H332
P260 , P261 , P264 , P270 , P271 , P280 , P301+P312 , P301+P330+P331 , P302+P352 , P303+P361+P353 , P304+P312 , P304+P340 , P305+P351+P338 , P310 , P312 , P321 , P322 , P330 , P363 , P405 , P501
Safety data sheet (SDS)
MSDS
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Niobium(V) bromide is the inorganic compound with the formula Nb2 Br10 . Its name comes from the compound's empirical formula , NbBr5 .[ 2] 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.[ 3] 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 :[ 4]
Nb2 O5 + 3.3 AlBr3 → 2 NbBr5 + 3.3 Al2 O3
A challenge with the latter method is the occurrence of NbOBr3 as an impurity.
References
External links
Niobium(II) Niobium(III) Niobium(IV) Niobium(V)
Salts and covalent derivatives of the
bromide ion
Br(−I) Br(−I,I) Br(I) Br(II) Br(I,V) Br(III) Br(IV) Br(V) Br(VII)