Moessbauer study of the solvation parameters of tin tetrahalides

According to Moessbauer spectroscopic measurements of the process SnX4+2 D reversible SnX4D2 k1=1.1+-0.3 min-1 and k2=0.06+-0.02 min-1 rate constants came about for solvation of tin tetrahalides in indifferent media on addition of donor-type solvents at 5 deg C. A heat of solvation of -4.0+-1.0 kcal/mole was determined for the solvation reaction of SnI4 with tetrahydrofuran. It was found that solvation proceeds in several steps. The equilibrium constants of every single steps in the system SnI4-THF at 5 deg C were determined. It was found that in the case of the same tin tetrahalide the equilibrium constant of the solvation process increases with the increasing donicity of the donor solvent, while the equilibrium constant of the solvatation of the various tin tetrahalides by tetrahydrofuran decreases with the increasing size of the halogen atom. (K.A.)