2011/08/31 by Joshua Barr, Joshua D. Barr, Charles Stafford +2
Engineering · Materials Science · Physics and Astronomy · #Atomic physics #Electron #HOMO/LUMO #Hamiltonian (control theory) #Molecular Junctions and Nanostructures #Molecule #Multipole expansion #Physics #Quadrupole #Quantum Dots Synthesis And Properties #Quantum and electron transport phenomena #Quantum mechanics #cond-mat.mes-hall #van der Waals force
paper · pdf · doi:10.1103/physrevb.86.115403
published as Phys. Rev. B 86, 115403 (2012) · 13 pages, 9 figures
openalex publication_date 2012/09/04 · arxiv created 2012/09/13 · arxiv updated 2015/03/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We develop a \ensuremathπ-electron effective field theory (\ensuremathπ-EFT) wherein the two-body Hamiltonian for a \ensuremathπ-electron system is expressed in terms of three effective parameters: the \ensuremathπ-orbital quadrupole moment, the on-site repulsion, and a dielectric constant. As a first application of this \ensuremathπ-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 \ensuremathπ-EFT to calculate the differential conductance spectrum of the prototypical benzenedithiol-Au single-molecule junction and the \ensuremathπ-electron contribution to the van der Waals interaction between benzene and a metallic electrode.