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Enhancing dissociative chemisorption of H2O on Cu(111) via vibrational excitation.

ABSTRACT: The dissociative chemisorption of water is an important step in many heterogeneous catalytic processes. Here, the mode selectivity of this process was examined quantum mechanically on a realistic potential energy surface determined by fitting planewave density functional calculations spanning a large configuration space. The quantum dynamics of the surface reaction were characterized by a six-dimensional model including all important internal coordinates of H(2)O and its distance to the surface. It was found that excitations in all three vibrational modes are capable of enhancing reactivity more effectively than increasing translational energy, consistent with the "late" transition state in the reaction path.

SUBMITTER: Jiang B

PROVIDER: S-EPMC3387087 | biostudies-other | 2012 Jun

REPOSITORIES: biostudies-other

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Enhancing dissociative chemisorption of H2O on Cu(111) via vibrational excitation.

Jiang Bin B Ren Xuefeng X Xie Daiqian D Guo Hua H

Proceedings of the National Academy of Sciences of the United States of America 20120608 26

The dissociative chemisorption of water is an important step in many heterogeneous catalytic processes. Here, the mode selectivity of this process was examined quantum mechanically on a realistic potential energy surface determined by fitting planewave density functional calculations spanning a large configuration space. The quantum dynamics of the surface reaction were characterized by a six-dimensional model including all important internal coordinates of H(2)O and its distance to the surface. ...[more]

PMID: 22685207

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