Electronic correlation in cyclic polyenes. Behavior of approximate coupled-pair theories for large rings
Chemical Physics
2009-11-07 v1
Abstract
We investigate the cyclic polyenes (annulenes) C_{M}H_{M}, described by the Pariser--Parr--Pople (PPP) model, by means of the approximate coupled-pair theories (ACP, ACPQ). For the systems with the spectroscopic value of the PPP resonance integral beta=2.5 eV, the ACP method breaks down for M >= 446, and the ACPQ method--for M>194. In the ACPQ method, for M>170, two close lying solutions have been observed that become quasi-degenerate for M >= 198. The results indicate that the ACP and ACPQ methods cannot be applied to the one-dimensional metallic case.
Keywords
Cite
@article{arxiv.physics/0208076,
title = {Electronic correlation in cyclic polyenes. Behavior of approximate coupled-pair theories for large rings},
author = {R. Podeszwa},
journal= {arXiv preprint arXiv:physics/0208076},
year = {2009}
}
Comments
4 pages, 4 figures, RevTeX4