Thermal Decomposition of [M(NH3)6][Fe(CN)6] (M = Ir, Rh) in Different Atmospheres. Crystal Structure of [Rh(NH3)6][Fe(CN)6]

The double complex salt [Rh(NH3)6][Fe(CN)6] has been structurally characterized. The thermal behavior of salt [Rh(NH3)6][Fe(CN)6] in reducing (He/H2), inert (He), and oxidizing (Ar/O2) atmospheres has been studied in detail. The intermediate product of the decomposition of double complex salts [M(NH3)6][Fe(CN)6] (M = Ir, Rh) has been found to be an X-ray amorphous polymer compound with the gross composition FeM(CN)5. The final product of the decomposition of [Rh(NH3)6][Fe(CN)6] in reducing and inert atmospheres is an ordered FeRh alloy. In an oxidizing atmosphere, a solid solution of Fe2O3 and Rh2O3 oxides is predominantly formed. The obtained data allow us to consider double complex salts as precursors for obtaining iron-iridium and iron-rhodium alloys or oxide systems based on them.