Theory and Simulation of Materials (THEOS), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
Facoltà di Informatica, Istituto di Scienze Computazionali, and National Center for Computational Design and Discovery of Novel Materials (MARVEL), Università della Svizzera italiana (USI), Via Giuseppe Buffi 13, CH-6900, Lugano, Switzerland.
Phys Rev Lett. 2019 Feb 8;122(5):050601. doi: 10.1103/PhysRevLett.122.050601.
We present a method for performing multithermal-multibaric molecular dynamics simulations that sample entire regions of the temperature-pressure (TP) phase diagram. The method uses a variational principle [Valsson and Parrinello, Phys. Rev. Lett. 113, 090601 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.090601] in order to construct a bias that leads to a uniform sampling in energy and volume. The intervals of temperature and pressure are taken as inputs and the relevant energy and volume regions are determined on the fly. In this way the method guarantees adequate statistics for the chosen TP region. We show that our multithermal-multibaric simulations can be used to calculate all static physical quantities for all temperatures and pressures in the targeted region of the TP plane. We illustrate our approach by studying the density anomaly of TIP4P/ice water.
我们提出了一种在温度-压强 (TP) 相图的整个区域中进行多温多压分子动力学模拟的方法。该方法使用变分原理 [Valsson 和 Parrinello，Phys. Rev. Lett. 113, 090601 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.090601] 来构建一个偏置，以在能量和体积上实现均匀采样。温度和压强的间隔被作为输入，相关的能量和体积区域则是实时确定的。通过这种方式，该方法保证了所选 TP 区域的足够统计数据。我们表明，我们的多温多压模拟可以用于计算 TP 平面目标区域中所有温度和压力下的所有静态物理量。我们通过研究 TIP4P/冰的密度异常来举例说明我们的方法。
