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arXiv · 1001.4882

High-order harmonic generation from polyatomic molecules including nuclear motion and a nuclear modes analysis

C. B. Madsen·M. Abu-samha·L. B. Madsen
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Abstract

We present a generic approach for treating the effect of nuclear motion in the high-order harmonic generation from polyatomic molecules. Our procedure relies on a separation of nuclear and electron dynamics where we account for the electronic part using the Lewenstein model and nuclear motion enters as a nuclear correlation function. We express the nuclear correlation function in terms of Franck-Condon factors which allows us to decompose nuclear motion into modes and identify the modes that are dominant in the high-order harmonic generation process. We show results for the isotopes CH$_4$ and CD$_4$ and thereby provide direct theoretical support for a recent experiment [Baker {\it et al.}, Science {\bf 312}, 424 (2006)] that uses high-order harmonic generation to probe the ultra-fast structural nuclear rearrangement of ionized methane.

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C. B. Madsen, M. Abu-samha, L. B. Madsen. 2010-03-26. High-order harmonic generation from polyatomic molecules including nuclear motion and a nuclear modes analysis. https://doi.org/10.1103/physreva.81.043413

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