EXTENDED CYANINE DYES

Extended cyanine dyes are attractive candidates for molecular switches , wires, and nonlinear optical devices. When dye width exceeds half th e confinement width for solitons (30 C atoms or less) cyanines should exhibit localization phenomena, i. e., double-minimum potentials with degenerate ground states. To investigate this phenomenon, we have synt hesized a number of dipyridocyanines DPyN, N = 1, 3, 5, 9... through a novel synthetic approach which allows considerable flexibility in end group attachment. Such molecules in principle provide entry into a nu mber of interesting molecular devices.