Correlaction Effects on the Band Gap of Conducting Polymers

  title={Correlaction Effects on the Band Gap of Conducting Polymers},
  • C.Q.Wu
  • Published 23 October 1992
  • Physics
By applying the projection technique to the computation of excitation energies, we study the correlation effects on the band gap of conducting polymers. In the presence of an additional electron or hole, the correlation induces a polarization cloud around the addi- tional particle, which forms a polaron. For the excitation energy of a polaron,there is a competition between a {\it loss} of the correla- tion energy in the ground state and a {\it gain} of polarization energy. For the Hubbard…