Synthesis and properties of [Rh(NH3)(5)Cl]PtCl4]

The improved method was developed for preparing the [Rh(NH3)(5)Cl]Cl-2 comp lex. The complex was used to synthesize the tetrachloroplatinato(II)chlorop entaamminerhodium(III) double salt. The solubility product of the salt was estimated to be 7 x 10(-8) (mol/l)(2) at 17 degrees C. Thermolysis of [Rh(N H3)(5)Cl] [PtCl4] in an atmosphere of hydrogen or helium gave a powdered 1 : 1 Pt-Rh solid solution as a final product. The crystallite sizes were det ermined from the broadening of the diffraction reflections: 90 and 170 Angs trom upon the calcination in hydrogen and helium, respectively.