Retrieval of spectral and dynamic properties from two-dimensional infrared pump-probe experiments

Abstract: We have developed a fitting algorithm able to extract spectral and dynamic properties of a three level oscillator from a two-dimensional infrared spectrum (2D-IR) detected in time resolved nonlinear experiments. Such properties go from the frequencies of the ground-to-first and first-to-second vibrational transitions (and hence anharmonicity) to the frequency-fluctuation correlation function. This last is represented through a general expression that allows one to approach the various strategies of modeling proposed in the literature. The model is based on the Kubo picture of stochastic fluctuations of the transition frequency as a result of perturbations by a fluctuating surrounding. To account for the line-shape broadening due to pump pulse spectral width in double-resonance measurements, we supply the fitting algorithm with the option to perform the convolution of the spectral signal with a Lorentzian function in the pump-frequency dimension. The algorithm is tested here o...

• Type: Journal
• Year: 2008
• Where: JCC
• Authors: Riccardo Chelli, Victor V. Volkov, Roberto Righini
• Keywords: Fitting Algorithm, Infrared Spectroscopy, JCC 2008, Two-dimensional Infrared Spectrum