Self-Assembled Electrooptic Thin Films with Remarkably Blue-Shifted Optical Absorption Based on an X-Shaped Chromophore

An "X-shaped" two-dimensional electrooptic (EO) chromophore with extended orthogonal conjugation was designed and synthesized. Self-assembled thin films of this chromophore were fabricated via layer-by-layer chemisorptive siloxane-based self-assembly. The films exhibit a dramatically blue-shifted optical maximum (325 nm) while maintaining a large EO response (chi33(2) approximately 232 pm/V at 1064 nm; r33 approximately 43 pm/V at 1550 nm).