Smith, LD and Dijkstra, AG orcid.org/0000-0003-2298-4736 (2019) Quantum dissipative systems beyond the standard harmonic model: Features of linear absorption and dynamics. Journal of Chemical Physics, 151 (16). 164109. ISSN 0021-9606
Abstract
Current simulations of ultraviolet-visible absorption lineshapes and dynamics of condensed phase systems largely adopt a harmonic description to model vibrations. Often, this involves a model of displaced harmonic oscillators that have the same curvature. Although convenient, for many realistic molecular systems, this approximation no longer suffices. We elucidate nonstandard harmonic and anharmonic effects on linear absorption and dynamics using a stochastic Schrödinger equation approach to account for the environment. First, a harmonic oscillator model with ground and excited potentials that differ in curvature is utilized. Using this model, it is shown that curvature difference gives rise to an additional substructure in the vibronic progression of absorption spectra. This effect is explained and subsequently quantified via a derived expression for the Franck-Condon coefficients. Subsequently, anharmonic features in dissipative systems are studied, using a Morse potential and parameters that correspond to the diatomic molecule H2 for differing displacements and environment interaction. Finally, using a model potential, the population dynamics and absorption spectra for the stiff-stilbene photoswitch are presented and features are explained by a combination of curvature difference and anharmonicity in the form of potential energy barriers on the excited potential.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2019 Author(s). This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in Smith, LD and Dijkstra, AG (Accepted: 2019) Quantum dissipative systems beyond the standard harmonic model: features of linear absorption and dynamics. J. Chem. Phys. 151, 164109 (2019) and may be found at https://doi.org/10.1063/1.5122896. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemistry (Leeds) > Physical Chemistry (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 08 Oct 2019 12:33 |
Last Modified: | 15 Nov 2019 11:51 |
Status: | Published |
Publisher: | American Institute of Physics |
Identification Number: | 10.1063/1.5122896 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:151854 |