Unoccupied orbital energies of 1,4-benzenedithiol and the HOMO–LUMO gap

Authors

Adam M. Scheer, University of Nebraska-LincolnFollow
Gordon A. Gallup, University of Nebraska - LincolnFollow
Paul Burrow, University of Nebraska - LincolnFollow

Date of this Version

2008

Citation

Published in Chemical Physics Letters 466 (2008), pp 131–135.

doi:10.1016/j.cplett.2008.10.057

Comments

Copyright © 2008 Elsevier B.V. Used by permission.

Abstract

The energies of the temporary anion states of 1,4-benzenedithiol (BDT) are determined by electron scattering and compared with those computed by density functional theory (DFT) and Hartree–Fock (HF) methods. Using semi-empirical scalings derived from the ionization energies and electron affinities of a series of phenyl–ethynyl compounds, we compute the HOMO–LUMO energy gap of BDT. We show that without such scalings the gap is substantially underestimated using DFT and overestimated using HF methods. Scaled gaps are also determined for several related compounds and compared with experimental measurements in the literature.