RuCl62

RuCl6^2- (hexachlororuthenate(IV)) is the hexachlorometallate anion [RuCl6]^{2-}. It contains ruthenium in the +4 oxidation state coordinated by six chloride ligands in an octahedral geometry, giving an overall 2− charge. The anion is known in salts with alkali metals, such as Na2[RuCl6], K2[RuCl6], and Cs2[RuCl6], which crystallize as ionic compounds with the [RuCl6]^{2-} unit surrounded by counterions.

In aqueous solution, the [RuCl6]^{2-} unit is stable under chloride-rich conditions. The hexachloro complex can be formed from ruthenium precursors in strongly oxidizing, chloride-containing media; excess chloride helps stabilize the hexacoordinate ruthenium(IV) species. The Ru–Cl bonds provide a robust octahedral framework characteristic of many hexachloro ruthenium complexes. The complex participates in redox chemistry, being interconvertible with other ruthenium chloride species under changing redox conditions, and can be further manipulated to prepare other ruthenium coordination compounds.

Applications and related species: RuCl6^{2-} serves as a representative hexachloro metalate in inorganic and coordination chemistry and acts as a synthetic precursor for producing more complex ruthenium chlorides and coordination systems. Related hexachloro metalates include hexachloroosmate(IV) and other MCl6^{2-} ions in the same family.

Safety: Handling requires standard laboratory precautions for ruthenium salts and halide-containing inorganic compounds and proper disposal according to hazardous waste guidelines.