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arXiv · 1606.06145

Vibrationally resolved UV/Vis spectroscopy with time-dependent density functional based tight binding

Robert Rüger·Thomas Niehaus·Erik van Lenthe·Thomas Heine·Lucas Visscher
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Abstract

We report a time-dependent density functional based tight-binding (TD-DFTB) scheme for the calculation of UV/Vis spectra, explicitly taking into account the excitation of nuclear vibrations via the adiabatic Hessian Franck-Condon (AH|FC) method with a harmonic approximation for the nuclear wavefunction. The theory of vibrationally resolved UV/Vis spectroscopy is first summarized from the viewpoint of TD-DFTB. The method is benchmarked against time-dependent density functional theory (TD-DFT) calculations for strongly dipole allowed excitations in various aromatic and polar molecules. Using the recent 3ob:freq parameter set of Elstner's group, very good agreement with TD-DFT calculations using local functionals was achieved.

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Robert Rüger, Thomas Niehaus, Erik van Lenthe, Thomas Heine, Lucas Visscher. 2016-11-01. Vibrationally resolved UV/Vis spectroscopy with time-dependent density functional based tight binding. https://doi.org/10.1063/1.4966918

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