The problem of the absolute configuration of optically active molecules is investigated with the aid of the Kirkwood theory of optical rotatory power. Absolute configurations are assigned to the enantiomorphs of 2,3-epoxybutane and 1,2-dichloropropane. The assignments are consistent with the established experimental configurational relationships between these compounds. The Fischer convention is confirmed as a structurally correct representation of absolute configuration. The magnitudes of the calculated rotations of the compounds are in reasonably good agreement with experiment. The theory accounts satisfactorily for the effect of temperature and solvent on the optical rotation of 1,2-dichloropropane.

The Born theory of optical activity in quantum-mechanical form is simplified with the aid of certain approximations. It leads to a simple expression for the rotatory parameter of an active molecule in terms of the geometrical configuration and the polarizability tensors of its constituent groups. Optical anisotropy of the component groups and inhibited internal rotation are found to play an important role in determining rotatory power. The proposed theory has points of similarity both with the polarizability theories of Gray, de Mallemann, and Boys and also with Kuhn's specialization of Born's classical theory of optical activity. To illustrate its use, the absolute configuration and the specific rotation of d-secondary butyl alcohol are calculated.