ELECTRONIC-STRUCTURES OF CIS-POLYACETYLENE

The electronic structures of two possible forms of the so-called cis-skeletal polyacetylene (cis-polyacetylene) are investigated on the basis of the tight-binding LCAO-SCF-MO method under the CNDO/2 version. The analyses of the total energies per unit cell, the π bond orders and the interatomic interaction energies as to the both forms predict the cis-transoid backbone for the cis-polyacetylene. The examination of the patterns of particular molecular orbitals of the hypothetical cis-polymer with equal C-C bond lengths also supports the cis-transoid form. © 1979.