Institute of Chemical Physics, Russian Academy of Sciences, 117977, GSP-1, Kosygin str. 4, Moscow, Russia.
J Phys Chem A. 2009 Aug 13;113(32):9065-74. doi: 10.1021/jp9036759.
The effect of an external force on the kinetics of diffusion-assisted escaping of Brownian particles from a potential well is analyzed in detail. The analysis is made within the two-state model (TSM) of the process which is known to be valid in the deep well limit in the absence of external force. The generalized variant of the TSM, taking into account the effect of the force, is shown to be quite accurate as well for some shapes of the well. Within the generalized TSM, simple expressions for the well depopulation kinetics and, in particular, for the escape rate are obtained. These expressions show that the effect of a force (F) manifests itself in the escape rate dependence on only one parameter phi = Fa/(2k(b)T), where a is the Onsager radius of the attractive part of the well U(r), defined by the relation |U(a)| approximately k(b)T. The limiting behavior of this dependence in the cases of weak and strong force is analyzed in detail. Possible applications as well as the relation of the results of the analysis to those obtained earlier are briefly discussed.
详细分析了外力对扩散辅助布朗粒子从势阱中逃逸的动力学的影响。该分析是在该过程的两态模型（TSM）内进行的，已知在不存在外力的深阱极限情况下 TSM 是有效的。考虑到力的影响的 TSM 的广义变体对于某些形状的阱也非常准确。在广义 TSM 内，获得了简单的阱排空动力学表达式，特别是逃逸率的表达式。这些表达式表明，力（F）的影响仅体现在逃逸率对一个参数 phi = Fa/(2k(b)T)的依赖性上，其中 a 是阱 U(r)的吸引力部分的 Onsager 半径，由关系 |U(a)| approximately k(b)T 定义。在弱力和强力的情况下，详细分析了这种依赖性的极限行为。简要讨论了可能的应用以及分析结果与先前获得的结果的关系。
