The Effect of Complex Anions on the Structure of Water

Abstract

The microscopic ionic volumes, v A, of complex inorganic anions, obtained from crystal unit cell volumes, as well as their standard molar volumes, $$ V_{\text{A}}^{\infty } $$ , in aqueous solutions serve to establish whether these anions are water-structure-breakers or -makers. This is done via correlations with well known criteria for such effects, namely the ionic viscosity B-coefficients and the structural entropies. Complex anions with charges z A are structure-breakers if v A > 0.1|z A| nm3·ion−1 or $$ V_{\text{A}}^{\infty } $$ > 35|z A|4/3 cm3·mol−1 and structure-makers if otherwise.