The recently developed first-principles linear-muffin-tin-orbital method for calculating the electronic structure of helical polymers is applied to polyacetylene. Total energies, charge densities, and energy bands are calculated for five different geometries of trans- and cis-polyacetylene. The dimerization of trans-polyacetylene is furthermore investigated and the configuration coordinate u0 is determined. It is analyzed whether the results can be explained with simple model Hamiltonians of the Su-Schrieffer-Heeger type.
 

Physical Review B, 33 8475-89, 1986.