STATISTICAL STRUCTURE OF SOLUBLE CONJUGATED POLYMERS .2. LOCALIZATION EFFECTS AND ELECTRON SELF-TRAPPING

We use a new approach we recently developed to deal with the properties of conjugated polymers in solution at finite temperature. Coupled electronic and conformational degrees of freedom of the chain are accounted for by introducing a configurational-dependent term in the electronic Hamiltonian. Fermionic properties are described by a Hückel Hamiltonian and a Monte Carlo simulation deals with the statistical conformational chain structure. The paper is focused on the localization properties of the π electrons located along the chain backbone. The localized versus extended character of the electronic states is measured upon variation of temperature. We further calculate the electronic density on the chain, 〈CiCi +〉 as carriers are added to the system through doping. Possibilities for self-trapping of the electrons arising from the coupling to the rotational modes are studied: local rigid regions containing additional electrons are predicted and are qualitatively described. © 1990 American Institute of Physics.