Electronic structure of Σ conjugated high polymers

Polysilane (PS), a typical σ-conjugated polymer, has recently attracted a great deal of attention from chemists and physicists because of its delocalized σ electrons along the skeleton. This paper discusses the electronic structure of Si skeleton high polymers systems, based on theoretical band calculations. 1D PS chains all have similar direct band structures, independently of the skeleton form and polymeric crystallization. The band-edge states are delocalized toward the backbone. 2D PS has a mixed band gap structure, which might allow non-linear conduction as well as complex adsorption edge. Ordered copolymerization introduces several characteristic features into the values of the band gaps and the electron distribution.