:Iridium tetroxide

{{chembox

| Name = Iridium(VIII) oxide

| ImageFile = Ruthenium-tetroxide-3D-balls.png

| ImageSize = 100px

| IUPACName = Iridium(VIII) oxide

| Section1 = {{Chembox Identifiers

| CASNo = 474103-25-8

| SMILES = O=[Ir](=O)(=O)=O

| StdInChI=1S/Ir.4O

| StdInChIKey = WIFDYPVIKSJTTM-UHFFFAOYSA-N

}}

| Section2 = {{Chembox Properties

| Ir=1 | O=4

| MeltingPtC = −267.15

}}

}}

Iridium tetroxide (IrO4, Iridium(VIII) oxide) is a binary compound of oxygen and iridium in oxidation state +8. This compound was formed by photochemical rearrangement of {{!(}}(η1-O2)IrO2{{)!}} in solid argon at a temperature of {{convert|6|K|C F}}. At higher temperatures, the oxide is unstable.{{cite journal|doi=10.1021/jp990388o|title=Reactions of Laser-Ablated Iridium Atoms with O2. Infrared Spectra and DFT Calculations for Iridium Dioxide and Peroxoiridium(VI) Dioxide in Solid Argon|year=1999|last1=Citra|first1=Angelo|last2=Andrew|first2=Lester|journal=J. Phys. Chem. A|volume=103|issue=21|pages=4182–4190|bibcode=1999JPCA..103.4182C}} The detection of the iridium tetroxide cation {{chem|IrO|4|+}} by infrared photodissociation spectroscopy with formal oxidation state +9 has been reported, the highest currently known of any element. However no salts are known, as attempted production of an Ir(IX) salt such as IrO4SbF6 did not result in anything.

References

{{Reflist|refs=

{{cite journal|doi=10.1002/anie.200902733|title=Formation and Characterization of the Iridium Tetroxide Molecule with Iridium in the Oxidation State +VIII|year=2009|last1=Gong|first1=Yu|last2=Zhou|first2=Mingfei|last3=Kaupp|first3=Martin|last4=Riedel|first4=Sebastian|journal=Angewandte Chemie International Edition|volume=48|issue=42|pages=7879–7883|pmid=19593837}}

{{cite journal |last1= Himmel |first1= D. |last2= Knapp |first2= C. |last3= Patzschke |first3= M. |last4= Riedel |first4= S. |title= How far can we go? Quantum-chemical investigations of oxidation state IX |journal= ChemPhysChem |volume= 11 |pages= 865–869 |year= 2010 |issue= 4 |doi= 10.1002/cphc.200900910 |pmid= 20127784}}

{{cite journal |title= Identification of an iridium-containing compound with a formal oxidation state of IX |first1= Guanjun |last1= Wang |first2= Mingfei |last2= Zhou |first3= James T. |last3= Goettel |first4= Gary J. |last4= Schrobilgen |first5= Jing |last5= Su |first6= Jun |last6= Li |first7= Tobias |last7= Schlöder |first8= Sebastian |last8= Riedel |journal= Nature |volume= 514 |pages= 475–477 |date= 23 October 2014 |issue= 7523 |doi= 10.1038/nature13795 |pmid= 25341786|bibcode= 2014Natur.514..475W |s2cid= 4463905 }}

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