Raman Study of Zinc Chloride Solutions

Raman studies of aqueous solutions of zinc chloride indicate the presence of Zn(H2O)6++, ZnCl(aq)+, linear ZnCl2(aq), and ZnCl4(H2O)2= in aqueous solutions less concentrated than ten molar. Ion concentrations are reported as functions of zinc chloride molarity. The tetrachloro complex dominates for stoichiometric zinc chloride concentrations between ∼0.5 to ∼10M with significant concentrations of ZnCl+ below ∼4M zinc chloride and ZnCl2 above ∼4M. For stoichiometric solutions greater than 10M, the evidence suggests a polymeric species or aggregate with structural characteristics similar to those found in the crystal.