Rhodium hexafluoride

{{Short description|Chemical compound with formula RhF₆}}

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| ImageFile =Rhodium(VI)-fluoride.svg

| ImageClass = skin-invert

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| IUPACName = rhodium(VI) fluoride

| OtherNames = rhodium hexafluoride

|Section1={{Chembox Identifiers

| CASNo = 13693-07-7

| PubChem = 20488757

| SMILES = F[Rh](F)(F)(F)(F)F

| InChI = 1/6FH.2Rh/h6*1H;;/q;;;;;;+6/p-6

| StdInChIKey = PDNXMXVYNVZBTD-UHFFFAOYSA-H

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|Section2={{Chembox Properties

| Rh=1 | F=6

| MolarMass = 216.91 g/mol

| Appearance = black crystalline solid

| Density = 3.71g/mL

| MeltingPt = ≈

| MeltingPtC = 70

| MeltingPt_ref =

| Solubility = }}

|Section3={{Chembox Hazards

| MainHazards =

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Rhodium hexafluoride, also rhodium(VI) fluoride, (RhF₆) is the inorganic compound of rhodium and fluorine. A black volatile solid, it is a highly reactive material which starts to slowly thermally decompose already at room temperature and a rare example of a rhodium(VI) compound. It is one of seventeen known binary hexafluorides.

Rhodium hexafluoride was discovered by American radiochemists in 1961, soon after the discovery of ruthenium hexafluoride.{{Cite journal |last=Chernick |first=Cedric L. |last2=Claassen |first2=Howard H. |last3=Weinstock |first3=Bernard |date=1961 |title=RHODIUM HEXAFLUORIDE |url=https://pubs.acs.org/doi/10.1021/ja01475a046 |journal=Journal of the American Chemical Society |volume=83 |issue=14 |pages=3165–3166 |doi=10.1021/ja01475a046 |issn=0002-7863|url-access=subscription }} It is prepared by reaction of rhodium metal with an excess of elemental fluorine:

:Rh + 3 F₂ → RhF₆

The RhF₆ molecule has octahedral molecular geometry. Consistent with its d³ configuration, the six Rh–F bond lengths are equivalent, being 1.824 Å. It crystallises in an orthorhombic space group Pnma with lattice parameters of a = 9.323 Å, b = 8.474 Å, and c = 4.910 Å.

Like some other metal fluorides, RhF₆ is highly oxidizing. It attacks glass, and can even react with elemental oxygen.{{cite journal |last1=Riedel |first1=Sebastian |last2=Kaupp |first2=Martin |year=2009 |title=The highest oxidation states of the transition metal elements |journal=Coordination Chemistry Reviews |volume=253 |issue=5–6 |pages=606–624 |publisher=Elsevier |doi=10.1016/j.ccr.2008.07.014 |url=http://144.206.159.178/ft/243/588116/14862785.pdf }}{{dead link|date=April 2018 |bot=InternetArchiveBot |fix-attempted=yes }}