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arXiv · 0706.1905

Quantum dynamics of N-methylacetamide studied by the vibrational configuration interaction method

Hiroshi Fujisaki·Kiyoshi Yagi·Kimihiko Hirao·John E. Straub
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Abstract

Vibrational energy transfer of the amide I mode of N-methylacetamide (NMA) is studied theoretically using the vibrational configuration interaction method. A quartic force field of NMA is constructed at the B3LYP/6-31G+(d) level of theory and its accuarcy is checked by comparing the resulting anharmonic frequencies with available theoretical and experimental values. Quantum dynamics calculations for the amide I mode excitation clarify the dominant energy transfer pathways, which sensitively depend on the anharmonic couplings among vibrational modes. A ratio of the anharmonic coupling to the frequency mismatch is employed to predict and interpret the dominant energy flow pathways.

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Hiroshi Fujisaki, Kiyoshi Yagi, Kimihiko Hirao, John E. Straub. 2007-06-13. Quantum dynamics of N-methylacetamide studied by the vibrational configuration interaction method. https://doi.org/10.1016/j.cplett.2007.06.067

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