Kappler, Julian and Hinrichsen, Victor B. and Netz, Roland R. (2019) NonMarkovian barrier crossing with twotimescale memory is dominated by the faster memory component. The European Physical Journal E, 42 (119). ISSN 12928941

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Official URL: http://dx.doiorg443.webvpn.fjmu.edu.cn/10.1140/e...
Abstract
We investigate nonMarkovian barriercrossing kinetics of a massive particle in one dimension in the presence of a memory function that is the sum of two exponentials with different memory times τ 1 and τ 2 . Our Langevin simulations for the special case where both exponentials contribute equally to the total friction show that the barrier crossing time becomes independent of the longer memory time if at least one of the two memory times is larger than the intrinsic diffusion time. When we associate memory effects with coupled degrees of freedom that are orthogonal to a onedimensional reaction coordinate, this counterintuitive result shows that the faster orthogonal degrees of freedom dominate barriercrossing kinetics in the nonMarkovian limit and that the slower orthogonal degrees become negligible, quite contrary to the standard timescale separation assumption and with important consequences for the proper setup of coarsegraining procedures in the nonMarkovian case. By asymptotic matching and symmetry arguments, we construct a crossover formula for the barrier crossing time that is valid for general multiexponential memory kernels. This formula can be used to estimate barriercrossing times for general memory functions for high friction, i.e. in the overdamped regime, as well as for low friction, i.e. in the inertial regime. Typical examples where our results are important include protein folding in the highfriction limit and chemical reactions such as protontransfer reactions in the lowfriction limit.
Item Type:  Article 

Additional Information:  arXiv.org > physics > arXiv:1907.12883 
Subjects:  Mathematical and Computer Sciences > Mathematics > Applied Mathematics 
Divisions:  Department of Mathematics and Computer Science > Institute of Mathematics 
ID Code:  2402 
Deposited By:  Monika Drueck 
Deposited On:  18 Feb 2020 10:56 
Last Modified:  20 Feb 2020 10:43 
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