title: The role of the ethynyl substituent on the π-π stacking affinity of benzene: a theoretical study.
abstract: Herein, we report a high-level theoretical study (SCS-RI-MP2(full)/aug-cc-pVTZ) examining the stacking affinity of 1,3,5-triethynylbenzene. The stacking properties of this compound are compared to those of benzene and 1,3,5-trifluorobenzene. The results indicate that the ethynyl substituent improves the stacking affinity of the arene, since the binding energies for the stacked ethynyl-substituted arene dimers are higher than those of both benzene and the fluoro-substituted arene. This interesting behaviour has been studied by examining the energetics, geometries and electron charge density features of the complexes. A query in the Cambridge Structural Database returned several X-ray crystal structures containing π-π stacking interactions of 1,3,5-triethynylaryls that strongly agree with the theoretical results.
authors.affiliation: Department of Chemistry, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma de Mallorca, Spain. xlc1986@gmail.com
authors.forename: Xavier
authors.initials: X
authors.lastname: Lucas
authors.forename: David
authors.initials: D
authors.lastname: Quiñonero
authors.forename: Antonio
authors.initials: A
authors.lastname: Frontera
authors.forename: Pere M
authors.initials: PM
authors.lastname: Deyà