Zheng Lianqing, Yang Wei
Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306, USA.
J Chem Phys. 2008 Sep 28;129(12):124107. doi: 10.1063/1.2982161.
Recently, we developed a generalized ensemble based free energy simulation technique, the simulated scaling (SS) method [Li et al., J. Chem. Phys. 126, 024106 (2007)]. In the SS simulations, random walks in the scaling parameter space are realized and free energy values can be conveniently estimated based on trial biasing weights. To improve free energy convergence in the SS simulations, we adopt a recent adaptive algorithm to systematically optimize the scaling parameter intervals; here, the optimization target is the round-trip rate between two end chemical states. As demonstrated in our model studies on the solvation of chloride ion and methane, free energy convergence can be greatly improved when the round-trip rates are accelerated.
最近，我们开发了一种基于广义系综的自由能模拟技术——模拟标度（SS）方法[Li等人，《化学物理杂志》126, 024106 (2007)]。在SS模拟中，实现了标度参数空间中的随机游走，并且可以基于试验偏差权重方便地估计自由能值。为了提高SS模拟中的自由能收敛性，我们采用了一种最近的自适应算法来系统地优化标度参数区间；这里，优化目标是两个末端化学状态之间的往返速率。正如我们对氯离子和甲烷溶剂化的模型研究所表明的，当往返速率加快时，自由能收敛性可以得到极大改善。
