title: Correlation of polarizabilities with Van der Waals interactions in pi-systems.
abstract: This work aims to (i) provide a semiquantitative relationship that can be used to estimate the binding energy, equilibrium separation, and potential energy surface (PES) for supermolecules consisting of benzene and small polycyclic aromatic hydrocarbons (PAHs) in parallel configuration and (ii) give a qualitative description of pi-pi interactions between PAHs. We compute the one-dimensional PES of benzene translated parallel to various PAHs within the framework of second-order Møller-Plesset (MP2) perturbation theory. For PAHs of small MW difference, we observe a linear correlation between the binding energy and the number of carbon atoms in the supermolecule. The PES of these supermolecules is fit to an (exp-6) function whose variables are subsequently used to derive a mass-centered potential energy function as a function of the number of carbon atoms in the supermolecule. The linear dependence of the binding energy in the supermolecular series examined here can be directly correlated to the average polarizability product of the supermolecule. Last, we consider the supermolecular series of benzene with n-polyacenes to study the convergence of pi-pi interactions between PAHs when their size is considerably different.
authors.affiliation: San Diego State University, 5500 Campanile Drive, San Diego, California 92182-1030, USA. zeinalip@ucy.ac.cy
authors.forename: Constantinos D
authors.initials: CD
authors.lastname: Zeinalipour-Yazdi
authors.forename: David P
authors.initials: DP
authors.lastname: Pullman
mesh_terms: D000873:Anthracenes / Q000737:chemistry; D001554:Benzene / Q000737:chemistry; D001665:Binding Sites; D002244:Carbon / Q000737:chemistry; D008958:Models, Molecular; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D000873:Anthracenes; D011084:Polycyclic Aromatic Hydrocarbons; D002244:Carbon; D001554:Benzene