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arXiv · 1512.00185

A semiclassical hybrid approach to linear response functions for infrared spectroscopy

Frank Grossmann
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Abstract

Based on the integral representation of the semiclassical propagator of Herman and Kluk (HK), and in the limit of high temperatures, we formulate a hybrid expression for the correlation function of infrared spectroscopy. This is achieved by performing a partial linearization inside the integral over the difference of phase space variables that occurs after a twofold application of the HK propagator. A numerical case study for a coupled anharmonic oscillator shows that already for a total number of only two degrees of freedom, one of which is treated in the simplified manner, a substantial reduction of the numerical effort is achieved.

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Frank Grossmann. 2015-12-01. A semiclassical hybrid approach to linear response functions for infrared spectroscopy. https://doi.org/10.1088/0031-8949%2F91%2F4%2F044004

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