Structural dependence of the pi-electron contributions to the optical second hyperpolarizability of linear conjugated organic molecules

Tight-binding (molecular orbital) models of conjugated organic molecules were used to predict structure-activity correlations for molecules with large electronic hyperpolarizabilities [1]. The dependence of the nonresonant second hyperpolarizability on chain length and molecular substituents was investigated. The calculations point out the influence of bond alternation and the presence of substitutional (and conjugation) “defects” on the size, sign, and chain length dependence of the molecular (and the bulk) hyperpolarizability. It is hoped that the calculations will provide guidance for future chemical synthesis by presenting strategies for systematically tuning the size and sign of the hyperpolarizability. © 1989 SPIE.

Duke Scholars

Author David N. Beratan Chemistry