View source for Chemistry:Iridium(III) bromide

{{Chembox
| ImageFile =IrBr3 unit cell.png
| ImageCaption = Crystal structure
|Section1={{Chembox Identifiers
 | CASNo=10049-24-8
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo_Comment = anhydride
|CASNo2=13464-83-0
|CASNo2_Comment=tetrahydrate
| CASNo2_Ref = {{cascite|correct|CAS}}
 | PubChem         = 82324
 | ChemSpiderID    = 74295
| EC_number = 233-174-3 
| StdInChI=1S/3BrH.Ir/h3*1H;/q;;;+3/p-3
| StdInChIKey = HTFVQFACYFEXPR-UHFFFAOYSA-K
|SMILES=Br[Ir](Br)Br
}}
|Section2={{Chembox Properties
 | Appearance= dark reddish-brown solid<ref name="H. J. Kandiner">{{Cite book |last=Kandiner |first=H. J. |url=https://books.google.com/books?id=mImABwAAQBAJ |title=Iridium |date=2013-09-03 |publisher=Springer-Verlag |isbn=978-3-662-12128-3 |language=de}}</ref>
|Ir=1|Br=3
 | Density= 6.82 g·cm<sup>−3</sup><ref name="Dale L. Perry">{{Cite book |last=Perry |first=Dale L. |url=https://books.google.com/books?id=SFD30BvPBhoC&pg=PA213 |title=Handbook of Inorganic Compounds |date=2016-04-19 |publisher=CRC Press |isbn=978-1-4398-1462-8 |language=en}}</ref>
|MeltingPt=
|BoilingPt=
 | Solubility= insoluble<ref name="H. J. Kandiner" />
 | SolubleOther= insoluble in acids and bases<ref name="H. J. Kandiner" />
}}
|Section8={{Chembox Related
| OtherCompounds=Iridium(II) bromide
| OtherCations=[[Chemistry:Ruthenium(III) bromide|Ruthenium(III) bromide]]<br />[[Chemistry:Rhodium(III) bromide|Rhodium(III) bromide]]<br />[[Chemistry:Osmium(III) bromide|Osmium(III) bromide]]<br />Platinum(III) bromide
| OtherAnions=Iridium(III) hydroxide<br />[[Chemistry:Iridium(III) chloride|Iridium(III) chloride]]<br />[[Chemistry:Iridium(III) iodide|Iridium(III) iodide]]
}}
}}

'''Iridium(III) bromide''' is a [[Chemistry:Bromide|bromide]] of [[Chemistry:Iridium|iridium]](III), with the chemical formula of IrBr<sub>3</sub>.

== Preparation ==

Iridium(III) bromide can be formed by reacting iridium(II) bromide and [[Chemistry:Bromine|bromine]]. Its tetrahydrate can be formed by reacting iridium dioxide dihydrate with [[Chemistry:Hydrobromic acid|hydrobromic acid]].<ref name="H. J. Kandiner" /> It can also be formed by the direct reaction of iridium and bromine at 8&nbsp;atm and 570&nbsp;°C.<ref name="Stanley E. Livingstone">{{Cite book |last=Livingstone |first=Stanley E. |url=https://books.google.com/books?id=_to_DQAAQBAJ&pg=PA1257 |title=The Chemistry of Ruthenium, Rhodium, Palladium, Osmium, Iridium and Platinum: Pergamon Texts in Inorganic Chemistry, Volume 25 |date=2017-01-31 |publisher=Elsevier |isbn=978-1-4831-5840-2 |language=en}}</ref>

== 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.<ref name="H. J. Kandiner" /> It crystallizes in a highly disordered layered structure of [[Chemistry:Aluminium chloride|aluminum(III) chloride]] or [[Chemistry:Chromium(III) chloride|chromium(III) chloride]] type, where the [[Chemistry:Monoclinic|monoclinic]] [[Unit cell|unit cell]] contains four [[Chemistry:Formula unit|formula unit]]s. As with [[Chemistry:Rhenium(III) chloride|rhenium(III) chloride]], [[Chemistry:Rhenium(III) bromide|rhenium(III) bromide]], α-[[Chemistry:Iridium(III) chloride|iridium(III) chloride]] and α-[[Chemistry:Ruthenium(III) chloride|ruthenium(III) chloride]], the disorder is due to the different stacking of the metal layers.<ref>{{Cite journal |last1=Brodersen |first1=K. |last2=Thiele |first2=G. |last3=Ohnsorge |first3=H. |last4=Recke |first4=I. |last5=Moers |first5=F. |date=1968-07-01 |title=Die struktur des IrBr3 und über die ursachen der fehlordnungserscheinungen bei den in schichtenstrukturen kristallisierenden edelmetalltrihalogeniden |url=https://dx.doi.org/10.1016/0022-5088%2868%2990194-X |journal=Journal of the Less Common Metals |language=de |volume=15 |issue=3 |pages=347–354 |doi=10.1016/0022-5088(68)90194-X |issn=0022-5088}}</ref> The light olive green tetrahydrate is slightly soluble in water but insoluble in [[Chemistry:Ethanol|ethanol]] and [[Chemistry:Ether|ether]]. When heated to 100&nbsp;°C, it turns dark brown with release of [[Chemistry:Water|water]] and decomposes to [[Chemistry:Iridium|iridium]] and [[Chemistry:Bromine|bromine]] at higher temperatures.<ref name="H. J. Kandiner" /> It reacts with [[Chemistry:Germanium dibromide|germanium dibromide]] in [[Chemistry:Hydrobromic acid|hydrobromic acid]] solution to form a compound containing Ir-Ge bond, and adding Cs<sup>+</sup> to it can separate Cs<sub>3</sub>[Ir(GeBr<sub>3</sub>)<sub>n</sub>Br<sub>6−n</sub>] (n=1, 2, 3).<ref>Antonov, P. G.; Agapov, I. A.; Manasevich, D. S. Iridium(III) complexation with germanium(II) compounds in aqueous hydrobromic acid solutions {{in lang|ru}}. ''Zhurnal Prikladnoi Khimii (Sankt-Peterburg)'', 1999. 72 (4): 556-559. ISSN: 0044-4618.</ref>

== References ==
{{reflist}}

{{Iridium compounds}}

[[Category:Iridium compounds]]
[[Category:Bromides]]

{{Sourceattribution|Iridium(III) bromide}}