PHOTOCHROMIC AND NONLINEAR OPTICAL-PROPERTIES OF C16H33-P3CNQ AND C16H33-Q3CNQ LANGMUIR-BLODGETT-FILMS

Z-ß-(1-hexadecyl-4-pyridinium)-α-cyano-4-styryldicyanomethanide (C16H33P3CNQ) and the quinolinium analogue, Z-ß-(1-hexadecyl-4-quinolinium)-α-cyano-4-styryldicyanomethanide (C16H33Q3CNQ), are photochromic. Their Langmuir-Blodgett (LB) films have narrow, switchable, charge transfer bands at 495 nm and 565 nm respectively with halfwidths at half-maximum of 27 and 22 nm and absorbances of 0.020 monolayer-1. At wavelengths which correspond to the absorption maxima there is little overlap of the bands and thus they are suitable for use in a multifrequency optical memory. The aligned LB films also exhibit second harmonic generation and have promising non-linear optical properties. © 1990.