![]() ![]() Due to the computational efficiency of the D3 correction schemes it is possible to perform DFT-D3 calculations with nearly the same computational effort as standard DFT calculations. The most recent DFT-D3(BJ) method differs from the original DFT-D3 essentially only in the damping function for short range interaction. Non-additive effects of dispersion interaction can be treated on the basis of three-body terms D3(ABC). ![]() The D3-dispersion correction to the DFT energy is calculated by summation over pair potentials. One of them is a damped empirical correction called DFT-D3 which was proposed by Grimme et al. In the last years much effort has been directed to the development of DFT methods that eliminate this shortage. Consequently, standard DFT methods are not suitable for the calculation of the adsorption of aromatic compounds. However, DFT has the well known shortcoming that it fails to describe dispersion effects. Density functional theory (DFT) is established as a standard method for quantum-chemical solid-state calculations. Therefore, a theoretical treatment of this process requires methods that provide an accurate description of these weak interactions. This holds in particular for the adsorption on the coinage metals copper, silver and gold. In addition, it was found that dispersion interaction plays a crucial role for the adsorption of large aromatic compounds on metal surfaces. The bonding between the surface and the adsorbate is an interplay between electrostatic interaction, including charge transfer (CT) to the surface, and covalent contributions. The adsorbed molecules often contain an aromatic framework that can be substituted with functional groups. The adsorption of organic molecules on metals is of great interest since the formation of thin films and self-assembled monolayers opens the way toward a functionalization of surfaces. Keywords: adsorption benzene coinage metals density functional theory dispersion correction template The observed trends for the surfaces and metals are consistent with the calculated adsorption energies. Vertical adsorbate–substrate distances are calculated and compared to previous theoretical results. The inclusion of three-center terms (PBE-D3(ABC)) leads to a slightly better agreement with the experiment in most cases. RevPBE-D3 and RevPBE-D3(BJ) tend to overestimate adsorption energies. PBE-D3, PBE-D3(BJ) and RPBE-D3 give similar results which exhibit a good agreement with experimental data. Variants of the Perdew–Burke–Ernzerhof functionals (PBE, RPBE and RevPBE) in combination with different versions of the dispersion correction (D3 and D3(BJ)) are compared. The adsorption of benzene on the M(111), M(100) and M(110) surfaces of the coinage metals copper (M = Cu), silver (M = Ag) and gold (M = Au) is studied on the basis of density functional theory (DFT) calculations with an empirical dispersion correction (D3). ![]()
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