Halide Ions in Mixed Solvent and Non-Aqueous Solutions

Halide Ions in Mixed Solvent and Non-Aqueous Solutions 

of course, natural from many points of view that aqueous solutions have been in the foreground for studies of electrolyte solutions, while studies of halide ion quadrupole relaxation in non-aque-ous solvents are quite few. However, studies of non-aqueous and mixed solvent systems are in certain respects highly relevant. For example, in order to test relaxation theories the possibility of making marked changes in solvent dipole moment, molecular size, dielectric constant, solvation number etc. should be very helpful. Also, the elucidation of certain general aspects of interactions and particle distributions in electrolyte solutions may be more easily achieved for non-aqueous systems. One such point is ion-pair formation, which for simple salts is not of great importance in water. Finally, of course, the quadrupole relaxation method may, as for aqueous solutions, be applied to more special problems such as ion solvation, complex formation etc. In studies of preferential solvation phenomena disorder effects in the first sphere may in certain cases be expected to lead to dramatic changes in the quadrupole relaxation rate. 

The first to use halogen quadrupole relaxation to consider these 

52 221] reported results on mainly water-methanol solutions of alkali 

It was concluded that the field gradient causing relaxation is, for these solvents, determined mainly by ion-solvent interactions and this was supported by a comparison with solvent dielectric constant. Similar results were obtained by Hall et al, [221] who investigated mixed 

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