Single-Bond Torsional Potentials in Conjugated Systems: A Comparison of ab Initio and Density Functional Results
Citations Over TimeTop 1% of 1997 papers
Abstract
The fully relaxed single-bond torsional potentials in typical conjugated systems were evaluated with the aid of ab initio self-consistent-field and Møller−Plesset second-order calculations and, additionally, with several recently developed variants of the density functional theory. For this systematic investigation, 1,3-butadiene, styrene, biphenyl, 2,2‘-bithiophene, 2,2‘-bipyrrole and 2,2‘-bifuran have been selected as model molecules. As representative examples for nonconjugated systems, the molecules n-butane and 1-butene have been treated at the very same calculational levels. For all conjugated molecules, the electron correlation corrections to the self-consistent-field torsional potentials, as obtained with the density functional methods, are dramatically different from those resulting from the more conventional Møller−Plesset second-order approximation. For those cases where experimental data for torsional barriers are available, the self-consistent-field and the Møller−Plesset second-order results agree reasonably, whereas the density functional results consistently predict too large barriers. This behavior is most probably caused by an overestimation of the stability of the planar π-systems by the density functional theory variants in question.
Related Papers
- → The Hydrolysis Mechanism of Formamide Revisited: Comparison Between ab initio, Semiempirical and DFT Results(1997)46 cited
- → Ab initio quantum-chemical study of the unimolecular pyrolysis mechanisms of acetic acid(1986)32 cited
- → Methanediol decomposition mechanisms: A study considering various ab initio approaches(1996)18 cited
- → An ab initio study on protonation of some substituted thiazole derivatives(2004)10 cited
- → The oximes of cyclopropenone, cyclopropanone and acetone and their O- and N-protonated forms. An ab initio and semiempirical quantum chemical study(1993)1 cited