Optical activity of crystals

Abstract
The analysis of the crystalline optical activity from the rotational invariance point of view allows one to quantitatively distinguish between molecular enantiomorphism, a polar longitudinal effect, and structural rotatory power. These three effects are discussed in connection with crystallographic symmetry. An alternative formulation of optical activity is presented. The so‐called specific rotativity is empirically shown to be dispersionless and almost insensitive to local field effects. In addition it is of the same order of magnitude for all known materials. These features are discussed in terms of a coupled oscillator model.