Thermochemistry on coordination behavior of praseodymium chloride hydrate with diethylammonium diethyldithiocarbamate

The complex of praseodymium chloride lower hydrate with diethylammonium diethyldithiocarbamate (D-DDC) has been synthesized conveniently in absolute alcohol and dry N-2 atmosphere. The title complex was identified as Et2NH2[Pr(S2CNEt2)(4)] by chemical and elemental analyses, the bonding characteristics of which were characterized by IR spectrum. The enthalpy of solution for praseodymium chloride hydrate and D-DDC in absolute alcohol at 298.15 K, and the enthalpy changes of liquid-phase reaction of formation for Et2NH2 [Pr(S2CNEt2)(4)] at different temperatures were determined by microcalorimetry. On the basis of experimental and calculated results, three thermodynamic parameters (the activation enthalpy, the activation entropy and the activation free energy), the rate constant and three kinetic parameters (the apparent activation energy, the pre-exponential constant and the reaction order) of liquid phase reaction of formation were obtained. The enthalpy change of the solid-phase title reaction at 298.15 K was calculated by a thermochemical cycle.