Derivatographic Studies on Transition Metal Complexes. I. Deaquation-Anation Reaction of Aquopentaamminechromium(III) Complexes

Abstract

Abstract By using a Derivatograph, the simultaneous analyses in TGA, DTA and DTG on the several aquopentaamminechromium(III) complexes were attempted. The enthalpy changes, ΔH, in the deaquation-anation processes of aquopentaamminechromium(III) nitrate, chloride, bromide, iodide, sulfate and sulfite were calculated as 11.9, 6.1, 9.0, 10.8, 13.8 and 12.8 kcal/mol, respectively, the activation energies, E\eweq, in the corresponding processes of the nitrate, chloride, bromide, sulfate and sulfite were obtained by the DTG curve analysis as 18, 28, 38, 36 and 33 kcal/mol, and those in the nitrate, chloride, bromide, iodide, sulfate and sulfite were obtained by the DTA curve analysis as 14, 25, 36, 19, 39 and 32 kcal/mol, respectively.