The Hubbard Model for One-Dimensional Solids

  • Anna Painelli
  • Alberto Girlando
Part of the NATO ASI Series book series (NSSB, volume 213)

Abstract

In recent years several unambiguous experimental evidences have been found stressing the relevance of electron-electron (e-e) interaction in one-dimensional (1D) solids, either charge-transfer salts1 or polymers.2 However there is not agreement between physicists on how to model e-e interaction in polymers, so that the effects of such interaction on the dimerization amplitude and on the band gap are still controversial.3–13 The Hubbard model14 has been generally adopted to investigate the role of e-e interaction in 1D solids. It is the solid state counterpart of the Pariser-Parr-Pople (PPP) model, widely tested and successfully applied in molecular physics. However, the electrons in isolated molecules experience an unscreened Coulomb repulsion, whereas in 1D solids the interaction between the electrons along a chain may be screened due to the presence of mobile electrons on neighboring chains. The applicability of Hubbard model to systems with highly screened potential still has to be settled.

Keywords

Polyacetylene 

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Anna Painelli
    • 1
  • Alberto Girlando
    • 2
  1. 1.Dept. of Chemical PhysicsPadova UniversityPadovaItaly
  2. 2.Inst. of Chemical PhysicsParma UniversityParmaItaly

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