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Coarse-grained interaction potentials for polyaromatic hydrocarbons

O. Anatole von Lilienfeld·Denis Andrienko
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Abstract

Using Kohn-Sham density functional theory (KS-DFT), we have studied the interaction between various polyaromatic hydrocarbon molecules. The systems range from mono-cyclic benzene up to hexabenzocoronene (hbc). For several conventional exchange-correlation functionals potential energy curves of interaction of the $π$-$π$ stacking hbc dimer are reported. It is found that all pure local density or generalized gradient approximated functionals yield qualitatively incorrect predictions regarding structure and interaction. Inclusion of a non-local, atom-centered correction to the KS-Hamiltonian enables quantitative predictions. The computed potential energy surfaces of interaction yield parameters for a coarse-grained potential, which can be employed to study discotic liquid-crystalline mesophases of derived polyaromatic macromolecules.

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O. Anatole von Lilienfeld, Denis Andrienko. 2005-12-09. Coarse-grained interaction potentials for polyaromatic hydrocarbons. https://doi.org/10.1063/1.2162543

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