Association of n-alcohols in non-polar solvents. Part I. The dielectric polarisations, apparent dipole moments, and near-infrared spectra of n-alcohols in carbon tetrachloride and cyclohexane

Abstract

Association of n-Alcohols in Non-polar Solvents. Part I. The Dielectric Polarisations, Apparent Dipole Moments, and Near-infrared Spectra of n-Alcohols in Carbon Tetrachloride and Cyclohexane By D. A. lbbitson and L. F. Moore,* Derby and District College of TechnologyDielectric constant, c, density, and near-infrared spectra of a series of solutions of graded concentration of n-alcohols in carbon tetrachloride and cyclohexane have been determined. Apparent dipole moments of the solutes have been calculated and solute polarisation, P,, evaluated as a function of alcohol weight fraction. Existence in solution of monomer only coincides with linear dependence of both t and P, on alcohol weight fraction. Positive and negative deviations of t and P, are explained by presence of effective amounts of linear dimer and trimer, and cyclic polymer, respectively.A N attempt has been made to resolve the controversy existing with regard to the mode of association of n-alcohols in non-polar solvents,l and to explain the nature of the solute polarisation (P,)-concentration plots for such solutions.2 That the latter plots are anomalous is well re~ognised,~ several workers reporting the occurrence of maxima or minima at relatively low concentrations,* and others finding the plots to be re~tilinear.~ In many cases, however, data are unavailable for solutions of sufficiently low concentration for monomer species only to exist. Although general agreement exists that the anomalous dielectric behaviour arises from solute association, discussion in terms of the structures of the species present is limited.6 Only Liebaert and Leroy 7 have attempted a quantitative interpretation in terms of a particular association model.In the present investigation dielectric constant, E, density, and neax-infrared spectra of a series of solutions of graded concentration of n-alcohols in carbon tetrachloride and cyclohexane have been determined. Solute polarisations have been calculated at each concentration and the plots of P, and c against alcohol weight fraction, w , examined and compared with the near-infrared spectra. Apparent dipole moments of the solutes have also been evaluated. I t is concluded that the lower polymers existing in solution are linear and the higher polymers, cyclic. EXPERIMENTAL Dipole Moments.-(a) Materials.The n-alcohols were dried over anhydrous magnesium sulphate for a t least 24 hr., and distilled from sodium immediately before use." Spectrosol " carbon tetrachloride and cyclohexane were dried as described previously.*

Hydrogen bonding interaction between ethyl methacrylate and alcohols in non-polar solvents: An FTIR study

“…Hydrogen bonded absorption band around 3354 cm 71 is observed for alcohols with n-heptane and alcohols with carbon tetrachloride systems. In the case of alcohols with benzene system an absorption band is observed at 3447 cm 71 [14]. Benzene produces lower OÀ ÀH stretching frequencies than other solvents no doubt to the tendency for the association with the electrons of the aromatic ring.…”

The Association of 3‐ethylpentanol‐3 in Carbon Tetrachloride from the Static Dielectric Permittivity and the Infrared Absorbance

“…at 25 "C due to the appearance of multimers with a great dipole moment. In view of the similar shape of the 1R spectrum [5, 61 and the (p2)app versus x plot [2,3,8,9] for different alcohols in alkanes and carbon tetrachloride at low concentrations we can probably extend the applicability of this model to other alcohols in alkanes and carbon tetrachloride in the low concentration range.…”

Physical behavior of some reaction media. Density, viscosity, dielectric constant, and refractive index changes of ethanol-cyclohexane mixtures at several temperatures

“…An attempt has been made to express these properties by means of single equations, wherein the temperature and composition effects are involved. Some physical properties of the above-mentioned binary mixtures have been previously reported in the literature (10)(11)(12)(13)(14). However, these studies have been made at very different composition or temperature ranges than those used in our kinetic experiments.…”