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arXiv · 1108.0021

Effective Field Theory of Interacting π-Electrons

Joshua D. Barr·Justin P. Bergfield·Charles A. Stafford
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Abstract

We develop a π-electron effective field theory (π-EFT) wherein the two-body Hamiltonian for a π-electron system is expressed in terms of three effective parameters: the π-orbital quadrupole moment, the on-site repulsion, and a dielectric constant. As a first application of this π-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 π-EFT to calculate the differential conductance spectrum of the prototypical benzenedithiol-Au single-molecule junction and the π-electron contribution to the van der Waals interaction between benzene and a metallic electrode.

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Joshua D. Barr, Justin P. Bergfield, Charles A. Stafford. 2012-09-13. Effective Field Theory of Interacting π-Electrons. https://doi.org/10.1103/physrevb.86.115403

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