Maintaining chromophore alignment in nonlinear optical materials via non-covalent interactions.

摘要

Recent developments in the field of nonlinear optics have led to demand for second-order NLO materials and devices with designed properties, both of the NLO response itself and of the physical properties of the device or material. Among the more elusive characteristics targeted in this field is that of temporal stability of the NLO response in organic and, especially, polymeric materials. Hydrogen bonding has long been used as a method of generating or stabilizing nanoscale molecular architectures. The work presented herein seeks to integrate these ideas by incorporating second-order NLO chromophores into a polymeric material in which long-term stability of the NLO response might be enhanced by intramolecular hydrogen bonding. A synthetic pathway has been developed, leading to the synthesis of a series of azobenzene-based chromophores, some of which exhibit a number of interesting properties. One of these chromophores has been incorporated into a polymeric material via metathesis polymerization using Grubbs-type catalysis. The resulting polymer has been characterized via spectroscopic and physical analysis, and attempts have been made to prepare high-quality thin films through a variety of casting techniques, in order to study the NLO properties of the material.