Correlations between theoretical and experimental Kerr constants of n-alkyl amides in solution in dioxan and water

Abstract

The theoretical molecular Kerr constants of eleven alkyl amides (related to formamide, acetamide and propionamide), calculated using bond polarisabilities and solution dipole moments, are compared with infinite dilution molecular Kerr constants determined in 1,4-dioxan at 298 K. Kerr effect data are also presented for several alkyl amides in solution in benzene, cyclohexane and water at 298 K. Theoretical molecular Kerr constants were found to be directly proportional to the corresponding experimental molecular Kerr constants measured in 1,4-dioxan. The optical polarisability tensors, associated with carbon–carbon and carbon–nitrogen single bonds and with carbon–hydrogen bonds of the amide alkyl groups, are not significantly changed in going from a dioxan to a water environment.