Vibrationally resolved electronic spectra including vibrational pre-excitation: Theory and application to VIPER spectroscopy

Jan von Cosel; Javier Cerezo; Daniela Kern-Michler; Carsten Neumann; Luuk J. G. W. van Wilderen; Jens Bredenbeck; Fabrizio Santoro; Irene Burghardt

doi:10.1063/1.4999455

arXiv · 1707.03476

Vibrationally resolved electronic spectra including vibrational pre-excitation: Theory and application to VIPER spectroscopy

Jan von Cosel·Javier Cerezo·Daniela Kern-Michler·Carsten Neumann·Luuk J. G. W. van Wilderen·Jens Bredenbeck·Fabrizio Santoro·Irene Burghardt

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Abstract

Vibrationally resolved electronic absorption spectra including the effect of vibrational pre-excitation are computed in order to interpret and predict vibronic transitions that are probed in the Vibrationally Promoted Electronic Resonance (VIPER) experiment [L. J. G. W. van Wilderen et al., Angew. Chem. Int. Ed. 53, 2667 (2014)]. To this end, we employ time-independent and time-dependent methods based on the evaluation of Franck-Condon overlap integrals and Fourier transformation of time-domain wavepacket autocorrelation functions, respectively. The time-independent approach uses a generalized version of the FCclasses method [F. Santoro et al., J. Chem. Phys. 126, 084509 (2007)]. In the time-dependent approach, autocorrelation functions are obtained by wavepacket propagation and by evaluation of analytic expressions, within the harmonic approximation including Duschinsky rotation effects. For several medium-sized polyatomic systems, it is shown that selective pre-excitation of particular vibrational modes leads to a red-shift of the low-frequency edge of the electronic absorption spectrum, which is a prerequisite for the VIPER experiment. This effect is typically most pronounced upon excitation of ring distortion modes within an aromatic pi-system. Theoretical predictions as to which modes show the strongest VIPER effect are found to be in excellent agreement with experiment.

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Jan von Cosel, Javier Cerezo, Daniela Kern-Michler, Carsten Neumann, Luuk J. G. W. van Wilderen, Jens Bredenbeck, Fabrizio Santoro, Irene Burghardt. 2017-07-11. Vibrationally resolved electronic spectra including vibrational pre-excitation: Theory and application to VIPER spectroscopy. https://doi.org/10.1063/1.4999455

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