Ruthenium(III) bromide
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| Identifiers | |
|---|---|
3D model (JSmol) | |
| ChemSpider | |
| ECHA InfoCard | 100.034.377 |
| EC Number |
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PubChem CID | |
| UNII | |
CompTox Dashboard (EPA) | |
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| Properties | |
| RuBr3 | |
| Molar mass | 340.782 g/mol |
| Structure | |
| orthorhombic[1] | |
| Pmmn, No. 59 | |
| octahedral | |
| Hazards | |
| GHS labelling: | |
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| Danger | |
| H314 | |
| P260, P264, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P363, P405, P501 | |
| Related compounds | |
Other anions | Ruthenium(III) chloride |
Other cations | Rhodium(III) bromide Iron(III) bromide Molybdenum(III) bromide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references | |
Ruthenium(III) bromide is a chemical compound of ruthenium and bromine with the formula RuBr3. It is a dark brown solid that decomposes above 400 °C.[2]
Preparation
Ruthenium(III) bromide can be prepared by the reaction of ruthenium metal with bromine at high temperature and pressure (720 K and 20 bar):[3]
- 2 Ru + 3 Br2 → 2 RuBr3
Structure
The crystal structures of ruthenium(III) bromide contain parallel (RuBr3)∞ columns. The compound undergoes a phase transition around 384 K (111 °C) from an ordered orthorhombic structure in space group Pnmm with alternating long and short Ru-Ru distances to a disordered hexagonal TiI3-like structure in space group P63/mcm with (on average) equal Ru-Ru distances.[1] In the disordered polymorph, the Ru-Ru distances are not believed to actually be equal but appear so due to a random distribution of two distinct column conformations. Both polymorphs consist of hexagonally close-packed bromide ions.[4]
References
- ^ a b Hillebrecht, H.; Ludwig, T.; Thiele, G. (2004). "About Trihalides with TiI3 Chain Structure: Proof of Pair Forming of Cations in β-RuCl3 and RuBr3 by Temperature Dependent Single Crystal X-ray Analyses". Zeitschrift für Anorganische und Allgemeine Chemie. 630 (13–14): 2199–2204. doi:10.1002/zaac.200400106.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 1082-1084. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8.
- ^ Housecroft, C. E.; Sharpe, A. G. (2008). Inorganic Chemistry (3rd ed.). Prentice Hall. p. 779. ISBN 978-0-13-175553-6.
- ^ Merlino, S.; Labella, L.; Marchetti, F.; Toscani, S. (2004). "Order−Disorder Transformation in RuBr3 and MoBr3: A Two-Dimensional Ising Model". Chem. Mater. 16 (20): 3895–3903. doi:10.1021/cm049235q.