AM1 CI STUDY OF A MOLECULAR RECTIFIER

Electronic and conformational studies on the push-pull system 4-quinol inium)-gamma-cyano-4-styrldicyanomethanide (C16H33-Q3CNQ) have recentl y been reported. Based on semi-empirical correlated PM3/ZINDO calculat ions, the rectifying properties of Langmuir-Blodgett films of these sp ecies have been interpreted in terms of a zwitterionic ground state. W e present a series of electronic and conformational studies on CH3-Q3C NQ based on semi-empirical calculations to assess solvent, external el ectric field and correlation effects. The ground state conformation ob tained is not of zwitterionic type, and a different interpretation of the intramolecular process of rectification of this system is presente d. (C) 1998 Elsevier Science B.V.