Effective field theory of interacting π electrons

  title={Effective field theory of interacting $\pi$ electrons},
  author={Joshua D. Barr and Justin P Bergfield and Charles A. Stafford},
  journal={Physical Review B},
We develop a \pi-electron effective field theory (\pi-EFT) wherein the two-body Hamiltonian for a \pi-electron system is expressed in terms of three effective parameters: the \pi-orbital quadrupole moment, the on-site repulsion, and a dielectric constant. As a first application of this \pi-EFT, we develop a model of screening in molecular junctions based on image multipole moments, and use this to investigate the reduction of the HOMO-LUMO gap of benzene. Beyond this, we also use \pi-EFT to… 
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