Synthesis, Structural and Nonlinear Optical Properties of 2-(3-Cyano-4-{5-[1-(2-Hydroxyethyl)-3,3-Dimethyl-l,3-Dihydro-Indol-2-ylidene]-Penta-l,3-dienyl}-5,5-Dimethyl-5#-Furan-2-ylidene)-Malononitrile

摘要

A chromophore for nonlinear optics with extended conjugation has been synthesized, and its structure determined from X-ray diffraction data. The compound crystallizes in the monoclinic system with the space group P2/ and Z = 4. The unit cell parameters are a = 10.7826(4) A, b = 14.5943(5) A, c = 15.3792(5) A and beta = 96.213(2)°. A thin film containing 5% of the chromophore in amorphous polycarbonate when poled at 180°C and 60 V/mum yields a maximum r_(33) value of 206 pm/V. This is seven times higher than the value found for the archetypical inorganic material, lithium niobate.