MCSCF study of polaron- and bipolaron-like defects in smallall-trans conjugated polyenes

Summary A Multiconfigurational Self-Consistent Field study of neutral, singly and doubly ionized C₄H₆, C₆H₈, C₈H₁₀, and C₁₀H₁₂ as model systems for polaron and bipolaron defects in polyacetylene has been carried out. In all computations a double zeta quality basis set was used. The post-Hartree-Fock computations were carried out in the complete active subspace and the fully optimized structures are reported. Comparison with SCF results reveals that the inclusion of electron correlation attenuates the double bond/single bond alternancy in conjugated polyenes as well as the charge waves associated with the cations.Dedicated to Prof. Klaus Ruedenberg