Electronic and conformational studies on the push-pull system Z-beta-(1-hexadecyl-4-quinolinium)-gamma-cyano-4-styrldicyanomethanide (C16H33-Q3CNQ) have recently been reported. Based on semi-empirical correlated PM3/ZINDO calculations, the rectifying properties of Langmuir-Blodgett films of these species have been interpreted in terms of a zwitterionic ground state. We present a series of electronic and conformational studies on CH3-Q3CNQ based on semi-empirical calculations to assess solvent, external electric field and correlation effects. The ground state conformation obtained is not of zwitterionic type, and a different interpretation of the intramolecular process of rectification of this system is presented. (C) 1998 Elsevier Science B.V.4322899
