Classical calculation of transient absorption spectra monitoring ultrafast electron transfer processes
Classical calculation of transient absorption spectra monitoring ultrafast electron transfer processes
Classical formulations are considered that allow for the calculation of time- and frequency-resolved pump−probe spectra of nonadiabatically coupled molecular systems. When the semiclassical Franck−Condon approximation in the theoretical framework of the doorway-window formalism is employed, various...
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Personal Name(s): | Uspenskiy, Igor |
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Strodel, Birgit / Stock, Gerhard (Corresponding author) | |
Contributing Institute: |
Strukturbiochemie; ICS-6 |
Published in: | Journal of chemical theory and computation, 2 (2006) 6, S. 1605 - 1617 |
Imprint: |
Washington, DC
2006
|
DOI: |
10.1021/ct6002127 |
PubMed ID: |
26627031 |
Document Type: |
Journal Article |
Research Program: |
Functional Macromolecules and Complexes |
Publikationsportal JuSER |
Classical formulations are considered that allow for the calculation of time- and frequency-resolved pump−probe spectra of nonadiabatically coupled molecular systems. When the semiclassical Franck−Condon approximation in the theoretical framework of the doorway-window formalism is employed, various first- and second-order expressions for the classical doorway and window functions are derived. Moreover, a classical analogue of the electronic dipole transition operator is employed. When established models describing ultrafast photoinduced electron transfer are adopted, it is found that the first-order approximations give rise to spurious structures of the time-resolved signal, which indicate that these approximations fail to correctly account for the averaging effect caused by finite pulses. The higher-order approximations, on the other hand, are shown to give a fairly accurate description of the transient absorption spectrum. By comparing to exact quantum-mechanical calculations, the merits and shortcomings of the various approaches as well as the generally achievable accuracy of a classical modeling of optical spectra is discussed. |