Iridium(III) bromide

Iridium(III) bromide
Crystal structure
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.030.146 Edit this at Wikidata
EC Number
  • 233-174-3
  • InChI=1S/3BrH.Ir/h3*1H;/q;;;+3/p-3
    Key: HTFVQFACYFEXPR-UHFFFAOYSA-K
  • Br[Ir](Br)Br
Properties
Br3Ir
Molar mass 431.929 g·mol−1
Appearance dark reddish-brown solid[1]
Density 6.82 g·cm−3[2]
insoluble[1]
Solubility insoluble in acids and bases[1]
Related compounds
Other anions
 Iridium(III) hydroxide
Iridium(III) chloride
Iridium(III) iodide
Other cations
 Ruthenium(III) bromide
Rhodium(III) bromide
Osmium(III) bromide
Platinum(III) bromide
Related compounds
 Iridium(II) bromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Iridium(III) bromide is a bromide of iridium(III), with the chemical formula of IrBr3.

Preparation

Iridium(III) bromide can be formed by reacting iridium(II) bromide and bromine. Its tetrahydrate can be formed by reacting iridium dioxide dihydrate with hydrobromic acid.[1] It can also be formed by the direct reaction of iridium and bromine at 8 atm and 570 °C.[3]

Properties

Iridium(III) bromide is a dark reddish-brown solid that is insoluble soluble in water, acids, and alkalis and decomposes to iridium(II) bromide on heating.[1] It crystallizes in a highly disordered layered structure of aluminum(III) chloride or chromium(III) chloride type, where the monoclinic unit cell contains four formula units. As with rhenium(III) chloride, rhenium(III) bromide, α-iridium(III) chloride and α-ruthenium(III) chloride, the disorder is due to the different stacking of the metal layers.[4] The light olive green tetrahydrate is slightly soluble in water but insoluble in ethanol and ether. When heated to 100 °C, it turns dark brown with release of water and decomposes to iridium and bromine at higher temperatures.[1] It reacts with germanium dibromide in hydrobromic acid solution to form a compound containing Ir-Ge bond, and adding Cs+ to it can separate Cs3[Ir(GeBr3)nBr6−n] (n=1, 2, 3).[5]

References

  1. ^ a b c d e f Kandiner, H. J. (2013-09-03). Iridium (in German). Springer-Verlag. ISBN 978-3-662-12128-3.
  2. ^ Perry, Dale L. (2016-04-19). Handbook of Inorganic Compounds. CRC Press. ISBN 978-1-4398-1462-8.
  3. ^ Livingstone, Stanley E. (2017-01-31). The Chemistry of Ruthenium, Rhodium, Palladium, Osmium, Iridium and Platinum: Pergamon Texts in Inorganic Chemistry, Volume 25. Elsevier. ISBN 978-1-4831-5840-2.
  4. ^ Brodersen, K.; Thiele, G.; Ohnsorge, H.; Recke, I.; Moers, F. (1968-07-01). "Die struktur des IrBr3 und über die ursachen der fehlordnungserscheinungen bei den in schichtenstrukturen kristallisierenden edelmetalltrihalogeniden". Journal of the Less Common Metals (in German). 15 (3): 347–354. doi:10.1016/0022-5088(68)90194-X. ISSN 0022-5088.
  5. ^ Antonov, P. G.; Agapov, I. A.; Manasevich, D. S. Iridium(III) complexation with germanium(II) compounds in aqueous hydrobromic acid solutions (in Russian). Zhurnal Prikladnoi Khimii (Sankt-Peterburg), 1999. 72 (4): 556-559. ISSN: 0044-4618.