Analysis of the chemical forms of iridium. Spectrophotometric determination of [Ir(NO2)6]3–, [Ir(NO2)Cl5]3– and [Ir(NO)Cl5]–

Abstract

A spectrophotometric method has been established for the determination of pentachloronitrosyliridate, [Ir(NO)Cl₅]^–, pentachloronitroiridate, [Ir(NO₂)Cl₅]^3–, and hexanitroiridate, [Ir(NO₂)₆]^3–. [Ir(NO)Cl₅]^– can be determined directly by colour development with sodium diphenylaminesulphonate, whereas the other two species may be converted into [Ir(NO)Cl₅]^– under different conditions and determined with the same reagent. A scheme is proposed for the determination of the three ions present in the same sample.