论文标题
通过非反应力场在恒定压力下的反应性分子动力学：将经验价键方法扩展到等温相质合体
Reactive molecular dynamics at constant pressure via non-reactive force fields: extending the Empirical Valence Bond method to the isothermal-isobaric ensemble
论文作者
论文摘要
经验价键（EVB）方法提供了一个合适的框架，可以通过非反应力场的耦合获得反应性电位。然而，耦合项的大多数实施功能形式都取决于复杂的空间坐标，这排除了用于凝结相系统的应力张量的计算，并防止了等倍疗和倍体（NPT）的EVB分子动力学的可能性。在这项工作中，我们利用取决于能量间隙的耦合术语，该术语定义为参与的非反应力场之间的能量差异，并得出适合计算的EVB应力张量的表达式。对这种新方法的实施进行了测试，以在非反应性水中溶剂化的单个反应性丙二醛的模型进行测试。 NPT集合中计算的密度和经典概率分布揭示了反应性潜力在低浓度溶液极限中的作用可忽略不计，从而证实了EVB模拟通常采用的标准近似值的有效性。
The Empirical Valence Bond (EVB) method offers a suitable framework to obtain reactive potentials through the coupling of non-reactive force fields. However, most of the implemented functional forms for the coupling terms depend on complex spatial coordinates, which precludes the computation of the stress tensor for condensed phase systems and prevents the possibility to carry out EVB molecular dynamics in the isothermal-isobaric (NPT) ensemble. In this work, we make use of coupling terms that depend on the energy gaps, defined as the energy differences between the participating non-reactive force fields, and derive an expression for the EVB stress tensor suitable for computations. Implementation of this new methodology is tested for a model of a single reactive malonaldehyde solvated in non-reactive water. Computed densities and classical probability distributions in the NPT ensemble reveals a negligible role of the reactive potential in the limit of low concentrated solutions, thus corroborating the validity of standard approximations customarily adopted for EVB simulations.
