"Quadrupolar" molecular nonlinear optics

Summary form only given. Measurement and exploitation of the various rotational invariants of the first hyperpolarisability tensor have been the subject of recent study. In particular, the quadrupolar and octupolar invariants may be of interest as new approaches to attaining noncentrosymmetric materials for application in second order nonlinear optics. In this work, we will examine the structure-property relationships for the J=2, or quadrupolar rotational invariant.