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Broadband infrared and Raman probes of excited-state vibrational molecular dynamics: simulation protocols based on loop diagrams.

ABSTRACT: Vibrational motions in electronically excited states can be observed either by time and frequency resolved infrared absorption or by off resonant stimulated Raman techniques. Multipoint correlation function expressions are derived for both signals. Three representations which suggest different simulation protocols for the signals are developed. These are based on the forward and the backward propagation of the wavefunction, sum over state expansion using an effective vibrational Hamiltonian or a semiclassical treatment of a bath. We show that the effective temporal (?t) and spectral (??) resolution of the techniques is not controlled solely by experimental knobs but also depends on the system dynamics being probed. The Fourier uncertainty ???t > 1 is never violated.

SUBMITTER: Dorfman KE

PROVIDER: S-EPMC3744248 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Broadband infrared and Raman probes of excited-state vibrational molecular dynamics: simulation protocols based on loop diagrams.

Dorfman Konstantin E KE Fingerhut Benjamin P BP Mukamel Shaul S

Physical chemistry chemical physics : PCCP 20130619 29

Vibrational motions in electronically excited states can be observed either by time and frequency resolved infrared absorption or by off resonant stimulated Raman techniques. Multipoint correlation function expressions are derived for both signals. Three representations which suggest different simulation protocols for the signals are developed. These are based on the forward and the backward propagation of the wavefunction, sum over state expansion using an effective vibrational Hamiltonian or a ...[more]

PMID: 23783120

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