Reaction ensemble molecular dynamics: direct simulation of the dynamic equilibrium properties of chemically reacting mixtures.
Reaction ensemble molecular dynamics: direct simulation of the dynamic equilibrium properties of chemically reacting mixtures.
复制标题
反应系综分子动力学：直接模拟化学反应混合物的动态平衡性质。
DOI：
--
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
B. Rice
中科院分区：
文献类型：
--
作者：
J. Brennan;M. Lísal;K. Gubbins;B. Rice
提出了一种研究化学反应混合物动力学的分子模拟方法。该方法使用的随机和动态模拟步骤的组合，允许模拟的热力学和运输性能。该方法将分子动力学模拟单元（称为动态单元）耦合到反应混合物模拟单元（称为控制单元），该反应混合物模拟单元基于反应系综蒙特卡罗（RxMC）方法制定，因此术语反应系综分子动力学。采用恒温分子动力学模拟方法，在动态池中计算了体系的热力学和输运性质。RxMC正向和反向反应步骤仅在对照池中进行，而分子动力学步骤在动态池和对照池中进行。控制单元，作为一个汇和源水库，保持在反应平衡条件下通过RxMC算法。反应系综分子动力学方法类似于巨正则系综分子动力学技术，同时使用渗透分子动力学方法的一些元素，因此模拟与真实的开放系统直接相关的条件。通过考虑氨合成反应N2 + 3 H2 2 N H3，评估了方法的准确度和稳定性<-->。它被证明是一个可行的方法来预测非理想环境的动态性能（特别是扩散）以及化学反应混合物的反应平衡的影响。
A molecular simulation method to study the dynamics of chemically reacting mixtures is presented. The method uses a combination of stochastic and dynamic simulation steps, allowing for the simulation of both thermodynamic and transport properties. The method couples a molecular dynamics simulation cell (termed dynamic cell) to a reaction mixture simulation cell (termed control cell) that is formulated upon the reaction ensemble Monte Carlo (RxMC) method, hence the term reaction ensemble molecular dynamics. Thermodynamic and transport properties are calculated in the dynamic cell by using a constant-temperature molecular dynamics simulation method. RxMC forward and reverse reaction steps are performed in the control cell only, while molecular dynamics steps are performed in both the dynamic cell and the control cell. The control cell, which acts as a sink and source reservoir, is maintained at reaction equilibrium conditions via the RxMC algorithm. The reaction ensemble molecular dynamics method is analogous to the grand canonical ensemble molecular dynamics technique, while using some elements of the osmotic molecular dynamics method, and so simulates conditions that directly relate to real, open systems. The accuracy and stability of the method is assessed by considering the ammonia synthesis reaction N2 +3 H2 <-->2N H3 . It is shown to be a viable method for predicting the effects of nonideal environments on the dynamic properties (particularly diffusion) as well as reaction equilibria for chemically reacting mixtures.