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Dynamics on the Double Morse Potential: A Paradigm for Roaming Reactions with no Saddle Points

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Abstract

In this paper we analyze a two-degree-of-freedom Hamiltonian system constructed from two planar Morse potentials. The resulting potential energy surface has two potential wells surrounded by an unbounded flat region containing no critical points. In addition, the model has an index one saddle between the potential wells. We study the dynamical mechanisms underlying transport between the two potential wells, with emphasis on the role of the flat region surrounding the wells. The model allows us to probe many of the features of the “roaming mechanism” whose reaction dynamics are of current interest in the chemistry community.

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Authors and Affiliations

  1. School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK

    Barry K. Carpenter

  2. Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA

    Gregory S. Ezra

  3. Institute of Electronic Structure and Laser, Foundation for Research and Technology–Hellas, and Department of Chemistry, University of Crete, Iraklion, 711 10, Greece

    Stavros C. Farantos

  4. Department of Chemistry and Biochemistry, La Salle University, 1900 West Olney Avenue, Philadelphia, PA, 19141, USA

    Zeb C. Kramer

  5. School of Mathematics, University of Bristol, Bristol, BS8 1TW, UK

    Stephen Wiggins

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  1. Barry K. Carpenter
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  2. Gregory S. Ezra
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  3. Stavros C. Farantos
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  4. Zeb C. Kramer
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  5. Stephen Wiggins
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Correspondence to Barry K. Carpenter.

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Carpenter, B.K., Ezra, G.S., Farantos, S.C. et al. Dynamics on the Double Morse Potential: A Paradigm for Roaming Reactions with no Saddle Points. Regul. Chaot. Dyn. 23, 60–79 (2018). https://doi.org/10.1134/S1560354718010069

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  • DOI: https://doi.org/10.1134/S1560354718010069

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