Alternating charge densities, peierls distortion, and charge-conjugation symmetry in correlated one-dimensional diatomic systems

The full-optimized-APSG approach based on the MC SCF technique is developed and applied to study ground-state properties of one-dimensional correlated systems. The effects of electron–electron interactions and bond relaxation are considered for the conjugated diatomic polymer; charge distribution and bond relaxation are calculated for the N = 50 chain within a wide range of site energy and e–e integral modulation involving the case of alternancy symmetry for diatomic systems. With relation to the results obtained, the problem of the neutral–ionic transition in mixed-stack crystals is discussed. © 1994 John Wiley & Sons, Inc.