ELECTRONIC-STRUCTURE OF THE LOWEST 1A1 AND 3B1 STATES OF CYCLOPROPENYLIDENE

Multiconfiguration self-consistent field calculations have been performed at several geometries on the lowest 1A1 and 3B1 states of cyclopropenylidene. The effects of hybridization and electron correlation are analyzed at the various geometries. These model prototype calculations reveal strong correlation effects in the aromatic singlet state as well as a singlet-triplet potential surface crossing which may play a role in the chemical reactivity of analogous chemical reactions involving insertion of singlet or triplet reagents into triple bonds. It is demonstrated that multiconfigurational wave functions are absolutely necessary to obtain a qualitative description of the two spin states of these unsaturated carbenes. © 1979, American Chemical Society. All rights reserved.