English
Related papers

Related papers: Geometrical Models of the Phase Space Structures G…

200 papers

We study the phase space geometry associated with index 2 saddles of a potential energy surface and its influence on reaction dynamics for $n$ degree-of-freedom (DoF) Hamiltonian systems. For index 1 saddles of potential energy surfaces…

Chaotic Dynamics · Physics 2015-05-13 Gregory S. Ezra , Stephen Wiggins

We consider the existence of invariant manifolds in phase space governing reaction dynamics in situations where there are no saddle points on the potential energy surface in the relevant regions of configuration space. We point out that…

Chemical Physics · Physics 2010-11-04 Gregory S. Ezra , Stephen Wiggins

A model Hamiltonian for the reaction CH$_4^+ \rightarrow$ CH$_3^+$ + H, parametrized to exhibit either early or late inner transition states, is employed to investigate the dynamical characteristics of the roaming mechanism. Tight/loose…

Chemical Physics · Physics 2015-06-18 F. A. L. Mauguière , P. Collins , G. S. Ezra , S. C. Farantos , S. Wiggins

Recently the phase space structures governing reaction dynamics in Hamiltonian systems have been identified and algorithms for their explicit construction have been developed. These phase space structures are induced by saddle type…

Chaotic Dynamics · Physics 2015-05-28 Unver Ciftci , Holger Waalkens

We provide a dynamical interpretation of the recently identified `roaming' mechanism for molecular dissociation reactions in terms of geometrical structures in phase space. These are NHIMs (Normally Hyperbolic Invariant Manifolds) and their…

In this article we present the influence of a Hamiltonian saddle-node bifurcation on the high-dimensional phase space structures that mediate reaction dynamics. To achieve this goal, we identify the phase space invariant manifolds using…

Chaotic Dynamics · Physics 2020-05-20 Víctor J. García-Garrido , Shibabrat Naik , Stephen Wiggins

We examine the phase space structures that govern reaction dynamics in the absence of critical points on the potential energy surface. We show that in the vicinity of hyperbolic invariant tori it is possible to define phase space dividing…

In this article, we review the analytical and numerical approaches for computing the phase space structures in two degrees-of-freedom Hamiltonian systems that arise in chemical reactions. In particular, these phase space structures are the…

Chaotic Dynamics · Physics 2020-04-14 Wenyang Lyu , Shibabrat Naik , Stephen Wiggins

Reaction rates of chemical reactions under nonequilibrium conditions can be determined through the construction of the normally hyperbolic invariant manifold (NHIM) [and moving dividing surface (DS)] associated with the transition state…

In this paper we unveil the geometrical template of phase space structures that governs transport in a Hamiltonian system described by a potential energy surface with an entrance/exit channel and two wells separated by an index-1 saddle.…

Chaotic Dynamics · Physics 2020-07-29 M. Katsanikas , V. J. García-Garrido , M. Agaoglou , S. Wiggins

In chemical reactions, trajectories typically turn from reactants to products when crossing a dividing surface close to the normally hyperbolic invariant manifold (NHIM) given by the intersection of the stable and unstable manifolds of a…

Chemical Physics · Physics 2020-11-10 Manuel Kuchelmeister , Johannes Reiff , Jörg Main , Rigoberto Hernandez

Chemical reactions in multidimensional systems are often described by a rank-1 saddle, whose stable and unstable manifolds intersect in the normally hyperbolic invariant manifold (NHIM). Trajectories started on the NHIM in principle never…

Chemical Physics · Physics 2020-02-25 Martin Tschöpe , Matthias Feldmaier , Jörg Main , Rigoberto Hernandez

We investigate the relation between the phase space structure of Hamiltonian and non-Hamiltonian deterministic thermostats. We show that phase space structures governing reaction dynamics in Hamiltonian systems map to the same type of phase…

Statistical Mechanics · Physics 2008-10-21 Gregory S. Ezra , Stephen Wiggins

We develop the geometrical, analytical, and computational framework for reactive island theory for three degrees-of-freedom time-independent Hamiltonian systems. In this setting, the dynamics occurs in a 5-dimensional energy surface in…

Chaotic Dynamics · Physics 2021-07-14 Vladimír Krajňák , Víctor J. García-Garrido , Stephen Wiggins

The rate of a chemical reaction can often be determined by the properties of a rank-1 saddle and the associated transition state separating reactants and products. We have found evidence that such rates can be controlled and even enhanced…

Chemical Physics · Physics 2021-09-28 Johannes Reiff , Robin Bardakcioglu , Matthias Feldmaier , Jörg Main , Rigoberto Hernandez

We review recent results on quantum reactive scattering from a phase space perspective. The approach uses classical and quantum versions of normal form theory and the perspective of dynamical systems theory. Over the past ten years the…

Quantum Physics · Physics 2010-10-15 Arseni Goussev , Roman Schubert , Holger Waalkens , Stephen Wiggins

The transformation of a system from one state to another is often mediated by a bottleneck in the system's phase space. In chemistry these bottlenecks are known as \emph{transition states} through which the system has to pass in order to…

Chaotic Dynamics · Physics 2015-06-15 Ünver Çiftçi , Holger Waalkens

We elucidate the escape properties of stars moving in the combined gravitational field of a binary system of two interacting dwarf spheroidal galaxies. A galaxy model of three degrees of freedom is adopted for describing the dynamical…

Astrophysics of Galaxies · Physics 2018-03-21 Euaggelos E. Zotos , Christof Jung

We study the bifurcation scenario of a three-degree-of-freedom Hamiltonian system, a model based on the Lagrange restricted 3-body problem: a test particle moving in the gravitational field of a pair of interacting dwarf galaxies. The phase…

Chaotic Dynamics · Physics 2026-02-11 Christof Jung , Francisco Gonzalez Montoya

A computational procedure that allows the detection of a new type of high-dimensional chaotic saddle in Hamiltonian systems with three degrees of freedom is presented. The chaotic saddle is associated with a so-called normally hyperbolic…

Chaotic Dynamics · Physics 2009-11-10 H. Waalkens , A. Burbanks , S. Wiggins
‹ Prev 1 2 3 10 Next ›