CALCULATION OF OPTICAL 2ND-HARMONIC SUSCEPTIBILITIES AND OPTICAL-ACTIVITY FOR CRYSTALS

A new generation of nearly first-principles calculations predicts both the linear and second-harmonic susceptibilities for a variety of insu lating crystals, including GaAs, GaP, AIAs, AIP, Se, alpha-quartz, and c-urea. The results are typically in agreement with experimental meas urements. The calculations have been extended to optical activity, wit h somewhat less success to date. The theory, based on a simple self-en ergy correction to the local density approximation, and results are re viewed herein. (C) 1994 John Wiley & Sons, inc.