Synthesis and thermal properties of double complex salt: chloropentaamminechromium(III) bis(oxalato)palladate

Double complex salt [Cr(NH₃)₅Cl][Pd(C₂O₄)₂] is synthesized for the first time. From the powder X-ray diffraction data it is found that the structure of the compound is triclinic with unit cell parameters: a = 3.225(3) Å, b = 10.290(6) Å, c = 11.390(6) Å, α = 116.5(2)°, β = 97.9(2)°, γ = 91.2(5)°, V = 334.5 Å³ (room temperature). The thermal properties are studied in detail in different gaseous atmospheres using powder X-ray diffraction, IR and Raman spectroscopy to identify intermediate and final thermolysis products. The sequence of stages of the thermal destruction of the double complex salt in inert and reducing atmospheres and the formation of the final thermolysis product (a double-phase mixture of palladium and chromium(III) oxide) are established.