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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Structure and energetics of azobenzene on Ag(111): benchmarking semiempirical dispersion correction approaches
G Mercurio1, E R McNellis, I Martin
1Institut für Bio- und Nanosysteme 3, Forschungszentrum Jülich, 52425 Jülich, Germany.
Abstract:
We employ normal-incidence x-ray standing wave and temperature programed desorption spectroscopy to derive the adsorption geometry and energetics of the prototypical molecular switch azobenzene at Ag(111). This allows us to assess the accuracy of semiempirical correction schemes as a computationally efficient means to overcome the deficiency of semilocal density-functional theory with respect to long-range van der Waals (vdW) interactions. The obtained agreement underscores the significant improvement provided by the account of vdW interactions, with remaining differences mainly attributed to the neglect of electronic screening at the metallic surface.
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