The principal focus of the project is to research and develop new polymeric materials based on molecular level design and solid state chemistry. The goals have been to develop electroactive polymers with novel electronic, optical and nonlinear optical properties.

This report describes our effort in the past three years on synthesis and characterization of novel photorefractive polymer system. Two major systems were developed, one of which combined the ionic transition metal complexes and a conjugated polymer backbone bearing NLO chromophores to manifest large photorefractive effect. Another is a molecular material containing oligothiophene and a nonlinear optical (NLO) chromophore. A large net optical gain (>200/cm) at a zero electric field was observed in the metal containing system. In the molecular system, a net optical gain of 83/cm and a diffraction efficiency of nearly 40% were obtained in a film made from this molecule under an applied field of 706 kv/cm. A fast response time of for the grating formation, 42 ms under 616 kv/cm, was observed.

This treatise is a compendium of papers based on invited talks presented at the American Chemical Society Symposium on Electroactive Polymers which covered nonlinear optical polymers and conducting polymers, the common denominator being the correlated pi-electron structures. The improved understanding of the consequences of pi-electron delocalization upon nonlinear optical properties and charge carrier dynamics has laid the foundation for the rapid development and application of the electroresponse of conjugated polymers. As a result, the area of electroactive and nonlinear optical polymers is emerging as a frontier of sCience and technology. It is a multidisciplinary field that is bringing together scientists and engineers of varied background to interface their expertise. The recent explosion of interest in this area stems from the prospect of utilizing nonlinear optical effects for optical switching and logic operations in optical computing, optical signal processing, optical sensing and optical fiber communications. Polymers and organic are rapidly becoming one of the major material classes for nonlinear optical applications along with multiple quantum wells, ferroelectrics and other oxides, and direct band-gap semiconductors. The reasons for this lie in the unique molecular structures of polymers and organics and the ability to molecularly engineer the architecture of these structures through chemical synthesis.