关于副本交换分子动力学模拟复杂化学反应的研究（英文）  

On the Simulation of Complex Reactions Using Replica Exchange Molecular Dynamics(REMD)

作　　者：辛亮[1,2] 孙淮 XIN Liang;SUN Huai(School of Chemistry and Chemical Engineering,Shanghai Jiao Tong University,Shanghai 200240,P.R.China;Materials Genome Initiative Center,Shanghai Jiao Tong University,Shanghai 200240,P.R.China;State Key Laboratory of Inorganic Synthesis and Preparative Chemistry,Jilin University,Changchun 130012,P.R.China)

机构地区：[1]上海交通大学化学化工学院,上海200240 [2]吉林大学无机合成与制备化学国家重点实验室,长春130012 [3]上海交通大学材料基因组联合研究中心,上海200240

出　　处：《物理化学学报》2018年第10期1179-1188,共10页Acta Physico-Chimica Sinica

基　　金：supported by the National Natural Science Foundation of China(21073119,21173146,21473112);National Basic Research Program of China(973)(2014CB239702)~~

摘　　要：本文研究用温度副本交换分子动力学(T-REMD)和哈密顿副本交换分子动力学(H-REMD)方法模拟复杂化学反应的问题。使用具有不同活化能和反应能的简单置换反应模型,我们检验了上述两种方法用来预测反应平衡产物的效率和应用范围。T-REMD方法对具有适度活化能(约<20 kcal·mol^(-1))或者反应能量(<3 kcal·mol^(-1))的放热反应是有效的。由于在相空间的不完整采样,对于同时具有高活化能和反应能量的反应其模拟效率有严重障碍,并且对于吸热反应问题更为显着。另一方面,H-REMD对一系列具有不同活化能的反应能的模型表现出色,与T-REMD相比,H-REMD可以使用更少的副本获得优异的结果。A complex reaction,such as combustion,polymerization,and zeolite synthesis,involves a large number of elementary reactions and chemical species.Given a set of elementary reactions,the apparent reaction rates,population of chemical species,and energy distribution as functions of time can be derived using deterministic or stochastic kinetic models.However,for many complex reactions,the corresponding elementary reactions are unknown.Molecular dynamics(MD)simulation,which is based on forces calculated by using either quantum mechanical methods or pre-parameterized reactive force fields,offers a possibility to probe the reaction mechanism from the first principles.Unfortunately,most reactions take place on timescales far above that of molecular simulation,which is considered to be a well-known rare event problem.The molecules may undergo numerous collisions and follow many pathways to find a favorable route to react.Often,the simulation trajectory can be trapped in a local minimum separated from others by high free-energy barriers;thus,crossing these barriers requires prohibitively long simulation times.Due to this timescale limitation,simulations are often conducted on very small systems or at unrealistically high temperatures,which might hinder their validity.In order to model complex reactions under conditions comparable with those of the experiments,enhanced sampling techniques are required.The replica exchange molecular dynamics(REMD)is one of the most popular enhance sampling techniques.By running multiple replicas of a simulation system using one or several controlling variables and exchanging the replicas according to the Metropolis acceptance rule,the phase space can be explored more efficiently.However,most published work on the REMD method focuses on the conformational changes of biological molecules or simple reactions that can be described by a reaction coordinate.The optimized parameters of such simulations may not be suitable for simulations of complex reactions,in which the energy changes are much more

关 键 词：副本交换 分子动力学 复杂反应 温度 哈密顿 

分 类 号：O645[理学—物理化学]