Solvation spectra. Part 11.—Cation dependence of the ultra-violet absorption spectra of iodide ions in solvents of low polarity

Abstract

The energies and temperature coefficients of the first ultra-violet absorption maxima for iodides in solvents of low polarity are interpreted in terms of ionic association. The band-energies correlate well with the Z-values of the solvents, except for carbon tetrachloride. Variation of the spectra with iodide concentration allows in one instance evaluation of the dissociation constant for the ion-pair. Competition experiments using added perchlorates lead to the determination of relative affinities of certain univalent cations for iodide.