Sodium and potassium tetraphenylborate solutions in water and 65% dioxan—water mixture—II. Spectrophotometric studies

Abstract

No evidence could be found from spectrophotometric measurements for the presence of ion-pairs in solutions of sodium or potassium tetraphenylborate, either in water or in a dioxan—water mixture of dielectric constant of 20 where such species may exist, according to the analysis of conductance data reported in the preceding paper. It is suggested that the tetraphenylborate ion spectra may arise from intramolecular transitions that are insensitive to environment. To make accurate spectrophotometric measurements on the low wavelength band of the tetraphenylborate ion (197 nm) corrections are necessary for the effect of stray light. A procedure using potassium hydroxide as cut-off filter was tested on potassium iodide which gas absorption bands in the same wavelength region as tetraphenylborate ion. Extinction coefficients of potassium iodide are reported at the band maxima.