Thermochemistry of alkali-metal hexachloro- and hexabromo-tungstates(IV) and -rhenates(IV)

Abstract

Enthalpies of hydrolysis or of oxidative hydrolysis are reported for the hexahalogenometallates(IV) K₂[WCl₆], K₂[WBr₆], Rb₂[WBr₆], Cs₂[WBr₆], K₂[ReCl₆], and K₂[ReBr₆], and for ReCl₄ and ReBr₄. Enthalpies of formation of these compounds have been calculated from these hydrolysis results. Halide-ion affinities of WCl₄, WBr₄, ReCl₄, and ReBr₄, and two-electron affinities of WCl₆ and WBr₆, have been estimated from these and other thermochemical results. These estimates have been made using the new direct-minimisation method of Jenkins and Pratt based on the Huggins and Mayer potential to assign the lattice energies of the hexahalogenometallate salts involved.