A benchmark comparison of σ/σ and π/π dispersion: the dimers of naphthalene and decalin, and coronene and perhydrocoronene.

ABSTRACT: The stacking interaction between π systems is a well-recognized structural motif, but stacking between σ systems was long considered of secondary importance. A recent paper points out that σ stacking can reach the energy of chemical bonds and concludes that "σ/σ and π/π interactions are equally important" (Fokin, A. F.; Gerbig, D.; Schreiner, P. R. J. Am. Chem. Soc. 2011, 133, 20036). Our analysis shows that strong dispersion interaction requires rigid subsystems and good fits of their repulsive potential walls, conditions which are satisfied for both graphenes and larger graphanes (perhydrographenes). Comparison of the dimerization energies of decalin and perhydrocoronene with those of the naphthalene and coronene dimers at the coupled cluster (CC) CCSD(T) level confirms the substantial σ

SUBMITTER: Janowski T 

PROVIDER: S-EPMC3488446 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature