Abstract

In the past decades, there have been extensive research efforts in developing new highly efficient organic materials with large second order susceptibilities because of their potential applications in optical signal processing and frequency conversion. Molecules possessing a large firstorder molecular hyperpolarizability ß are an essential prerequisite for achieving large macroscopic susceptibilities χ⁽²⁾. The molecular nonlinearity of the classical, nonlinear optically active molecule, which usually contains an electron donor and an electron acceptor connected by a π-conjugated core, can be enhanced by increasing the electron donor or electron acceptor strength, elongating the length of the conjugated core, and reducing the ground state aromatic character.

© 1996 IEEE