Solitons and Isomerization by Doping in Cis-Polyacetylene

Abstract

Solitons (localized objects) in cis-polyacetylene are examined by bosonization of electron operators and semiclassical treatment of the bosonized operators, where some parts of Coulomb interactions are taken into account. There are three types of soliton solutions; a polaron, a charge bisoliton and a spin bisoliton. Among them an isolated polaron seems to be stable in a doped substance. Cis-trans isomerization by doping is described in terms of such solitons. The region between dopants sufficiently close isomerizes; the largest dopant distance to isomerize is about 21 lattice spacings.