title: Effect of self-interaction error in the evaluation of the bond length alternation in trans-polyacetylene using density-functional theory.
abstract: The calculation of the bond-length alternation (BLA) in trans-polyacetylene has been chosen as benchmark to emphasize the effect of the self-interaction error within density-functional theory (DFT). In particular, the BLA of increasingly long acetylene oligomers has been computed using the Møller-Plesset wave-function method truncated at the second order and several DFT models. While local-density approximation (LDA) or generalized gradient corrected (GGA) functionals strongly underestimate the BLA, approaches including self-interaction corrections (SIC) provide significant improvements. Indeed, the simple averaged-density SIC scheme (ADSIC), recently proposed by Legrand et al. [J. Phys. B 35, 1115 (2002)], provides better results for the structure of large oligomers than the more complex approach of Krieger et al. [Phys. Rev. A 45, 101 (1992)]. The ADSIC method is particularly promising since both the exchange-correlation energy and potential are improved with respect to standard LDA/GGA using a physically appealing correction, through a different route than the more popular approach through the Hartree-Fock exchange inclusion within the hybrid functionals.
authors.affiliation: Ecole Nationale Supérieure de Chimie de Paris (ENSCP), Laboratoire d'Electrochimie et Chimie Analytique, Unité Mixte de Recherche (UMR) Centre National de la Recherche Scientifique (CNRS)-ENSCP n 7575, F-75231 Paris 05, France.
authors.forename: I
authors.initials: I
authors.lastname: Ciofini
authors.forename: C
authors.initials: C
authors.lastname: Adamo
authors.forename: H
authors.initials: H
authors.lastname: Chermette