Molecular polarisability and internal rotation in the alkyl chloride series

Abstract

The molar Kerr constants and dipole moments, measured at infinite dilution in carbon tetrachloride, of t-butyl, ethyl, n-propyl, n-butyl, n-pentyl, and n-hexyl chloride are recorded. Inductive effects in these molecules are briefly discussed. Estimates of the anisotropic polarisability of the C–Cl bond in t-butyl and ethyl chloride are obtained. Molar Kerr constants of the n-alkyl chlorides lie in the range +56 to 62 × 10–12. Expectation values of the molar Kerr constants, obtained by a treatment previously applied to n-alkyl bromides and iodides, are in excellent agreement with experiment. For n-propyl chloride, the gauche–trans energy difference is found to be +0·14± 0·1 kcal./mole.