Rhodium hexafluoride
Rhodium hexafluoride, also rhodium fluoride, 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 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. It is prepared by reaction of rhodium metal with an excess of elemental fluorine:
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.