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This article is cited in 5 scientific papers (total in 5 papers)
Special Issue: Nonlinear Dynamics in Chemical Sciences: Part II
Classical and Quantum Dynamical Manifestations of Index-2
Saddles: Concerted Versus Sequential Reaction Mechanisms
Priyanka Pandeya, Shibabrat Naikb, Srihari Keshavamurthya a Department of Chemistry, Indian Institute of Technology,
Kanpur, 208016 Uttar Pradesh, India
b School of Mathematics, University of Bristol,
Fry Building, Woodland Road,
BS8 1UG Bristol, United Kingdom
Abstract:
The presence of higher-index saddles on a multidimensional potential energy surface
is usually assumed to be of little significance in chemical reaction dynamics. Such a viewpoint
requires careful reconsideration, thanks to elegant experiments and novel theoretical approaches
that have come about in recent years. In this work, we perform a detailed classical and quantum
dynamical study of a model two-degree-of-freedom Hamiltonian, which captures the essence of
the debate regarding the dominance of a concerted or a stepwise reaction mechanism. We show
that the ultrafast shift of the mechanism from a concerted to a stepwise one is essentially a
classical dynamical effect. In addition, due to the classical phase space being a mixture of regular
and chaotic dynamics, it is possible to have a rich variety of dynamical behavior, including a
Murrell – Laidler type mechanism, even at energies sufficiently above that of the index-2 saddle.
We rationalize the dynamical results using an explicit construction of the classical invariant
manifolds in the phase space.
Keywords:
reaction mechanisms, index-2 saddles, classical-quantum correspondence, dynamic
Murrell-Laidler, invariant manifolds, concerted and sequential reactions.
Received: 10.09.2020 Accepted: 28.10.2020
Citation:
Priyanka Pandey, Shibabrat Naik, Srihari Keshavamurthy, “Classical and Quantum Dynamical Manifestations of Index-2
Saddles: Concerted Versus Sequential Reaction Mechanisms”, Regul. Chaotic Dyn., 26:2 (2021), 165–182
Linking options:
https://www.mathnet.ru/eng/rcd1109 https://www.mathnet.ru/eng/rcd/v26/i2/p165
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Abstract page: | 77 | References: | 13 |
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