Influence of solvents on broad band integrated absorption intensity

Abstract

The integrated absorption intensity (A_obs) has been determined for the broad band absorption in the far infrared region of t-butyl bromide and nitrobenzene in a variety of polar and non-polar solvents, and the equation A_obs=av has been found to be adequate where v is the volume concentration of the polar solute, and the value of “a” depends slightly on the solvent. From measurements on solutions, the A_obs value for the pure solute may be deduced and, when the solvent is inert, such as cyclohexane, the extrapolated value is in adequate agreement with that of the pure liquid. As the electronic polarizability of the solvent increases, the extrapolated A_obs value appears to increase above the value for the pure liquid, although the change is not as appreciable as has been previously believed. It would seem for the results described here that the value of A_obs is more sensitive to the polarizability of the solvent than the magnitude of the dipole moment of the solvent.