Standard enthalpy of formation of bis(diethyldithiocarbamato)copper(II) at 298 K and the copper–sulphur bond energy

Abstract

Solution calorimetry has been employed to determine the standard enthalpy of formation of bis(diethyldithiocarbamato)copper(II) at 298 K, ΔH_f^⊖[Cu(S₂CNEt₂)₂,c]=–17.70 ± 9.39 kJ mol^–1. Thermochemical measurements are based on a ligand-exchange reaction, in dimethylformamide as solvent, involving the displacement of pentane-2,4-dionate in bis(pentane-2,4-dionato)copper(II) by the diethyldithiocarbamate anion. The homolytic and heterolytic copper–sulphur bond-enthalpy contributions are assessed as 143 ± 13 and 678 ± 13 kJ respectively.