Escape rates in bistable systems with position-dependent friction coefficients

Compiani, Mario
January 1993
Journal of Chemical Physics;1/1/1993, Vol. 98 Issue 1, p602
Academic Journal
In this paper we consider the generalization of the Kramers’ model of chemical reactions to the case that the friction coefficient γ(x) depends on the reaction coordinate x. Extending previous efforts the escape rate is exactly evaluated in the high-friction limit imposing on γ(x) much milder conditions than used so far in the literature. The ensuing rate retains the Kramers’ form and reproduces the renormalization effect of the damping coefficient which has been reported in laboratory experiments on chemical reactions. The origin of variable friction coefficients is then discussed within the framework of a multidimensional Markovian model and ascribed to the nonlinear coupling of the reaction coordinate with faster auxiliary variables. Finally, the implications of our results for the rate of ligands migration in proteins are briefly considered.


Related Articles

  • Kinetic transitions in diffusion-reaction space. Kozak, John J.; Davidson, Russell // Journal of Chemical Physics;10/1/1994, Vol. 101 Issue 7, p6101 

    In this paper we study how the strength and range of the potential function v(r) governing the down-range motion of a diffusing coreactant A with respect to a stationary target molecule B influence the efficiency of the irreversible diffusion-reaction process: A+B→C. This problem is...

  • Application of the theory of Markov chains to model heat and mass transfer between stochastically moving particulate and gas flows. Mizonov, V.; Berthiaux, H.; Arlabosse, P.; Djerroud, D. // Granular Matter;Jun2008, Vol. 10 Issue 4, p335 

    A cell model to describe heat and mass transfer between two media, one or both of which are involved in stochastic motion, is proposed. The model consists of two chains of cells to describe 1D stochastic motion of the flows. Each couple of corresponding cells experiences heat and mass exchange...

  • APPLICATION OF DISCRETE STOCHASTIC MODELS FOR CHEMICAL KINETICS. BOBKOV, S. P.; BOBKOVA, E. S.; RYBKIN, V. V. // Izvestiya Vysshikh Uchebnykh Zavedenii. Seriya Khimiya i Khimich;2012, Vol. 55 Issue 9, p35 

    Attempts of stochastic approach application based on the theory of discrete Markov chains to modeling chemical reaction kinetics were considered. The description of chemically reacting system in the terms of the proposed mathematical tool was proposed.

  • A comparison of composition and sequence distribution of p(AM-MADQUAT) prepared by solution and inverse microemulsion polymerization. Zhang Aiqin; Shen Yinghua; Zhang Xiangying; Han Lingcui; Wang Zhizhong // Journal of Polymer Research;Jan2010, Vol. 17 Issue 1, p11 

    Acrylamide (AM)/2-(methacryloyloxy)ethyltrimethylammonium chloride (MADQUAT) copolymers were prepared by solution and inverse microemulsion polymerization using ammonium persulfate ((NH4)2S2O8)/sodium hydrosulfite (NaHSO3) as redox initiator at 30 °C. The comonomer reactivity ratios,...

  • A modified next reaction method for simulating chemical systems with time dependent propensities and delays. Anderson, David F. // Journal of Chemical Physics;12/7/2007, Vol. 127 Issue 21, p214107 

    Chemical reaction systems with a low to moderate number of molecules are typically modeled as discrete jump Markov processes. These systems are oftentimes simulated with methods that produce statistically exact sample paths such as the Gillespie algorithm or the next reaction method. In this...

  • Identification of slow molecular order parameters for Markov model construction. Pérez-Hernández, Guillermo; Paul, Fabian; Giorgino, Toni; De Fabritiis, Gianni; Noé, Frank // Journal of Chemical Physics;Jul2013, Vol. 139 Issue 1, p015102 

    A goal in the kinetic characterization of a macromolecular system is the description of its slow relaxation processes via (i) identification of the structural changes involved in these processes and (ii) estimation of the rates or timescales at which these slow processes occur. Most of the...

  • Simulating oligomerization at experimental concentrations and long timescales: A Markov state model approach. Kelley, Nicholas W.; Vishal, V.; Krafft, Grant A.; Pande, Vijay S. // Journal of Chemical Physics;12/7/2008, Vol. 129 Issue 21, p214707 

    Here, we present a novel computational approach for describing the formation of oligomeric assemblies at experimental concentrations and timescales. We propose an extension to the Markovian state model approach, where one includes low concentration oligomeric states analytically. This allows...

  • Statistics of copolymer sequences obtained by polymeranalogous reactions of homopolymer globules. Kuchanov, S. I.; Zharnikov, T. V.; Khokhlov, A. R. // European Physical Journal E -- Soft Matter;Feb2003, Vol. 10 Issue 2, p93 

    : For the first time the macrokinetics of polymeranalogous reaction in a homopolymer globule is considered theoretically. Using mathematical apparatus of the theory of markovian stochastic processes we examined the statistical characteristics of the chemical structure of the emerging copolymers....

  • Communications: Can one identify nonequilibrium in a three-state system by analyzing two-state trajectories? Amann, Christian P.; Schmiedl, Tim; Seifert, Udo // Journal of Chemical Physics;1/28/2010, Vol. 132 Issue 4, p041102 

    For a three-state Markov system in a stationary state, we discuss whether, on the basis of data obtained from effective two-state (or on-off) trajectories, it is possible to discriminate between an equilibrium state and a nonequilibrium steady state. By calculating the full phase diagram we...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics