Anisometric molecules in dense fluids

Abstract

The orientational contributions to the Kerr constant (electric birefringence) in dilute solutions are calculated. These are the alignment of the polarizability tensors of the solutes (calculated in a previous article in this series), and the orientation of their permanent moments, which is also considered here. The model is that where each anisometric molecule is considered as embedded in an ellipsoïdal cavity digged in an isotropic continuum which represents the non-birefringent solvent. The final formula which is obtained is identical to that for dilute gases, except that the polarizability tensors in vacuo must be replaced by ‘effective incremental polarizability tensors’ α* previously defined in this Series, and that the permanent dipole components must be multiplied by corresponding elements of the tensorial internal field factor.