Quantum Drude oscillator model of atoms and molecules: Many-body polarization and dispersion interactions for atomistic simulation
Quantum Drude oscillator model of atoms and molecules: Many-body polarization and dispersion interactions for atomistic simulation
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DOI：
10.1103/physrevb.87.144103
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发表时间：
2013-04-15
影响因子：
3.7
通讯作者：
Martyna, Glenn J.
中科院分区：
文献类型：
--
作者：
Jones, Andrew P.;Crain, Jason;Martyna, Glenn J.
处理多体极化和色散相互作用现在被认为是达到揭示复杂系统中新物理所需的原子建模水平的关键因素。量子德鲁德振子(QDO)是一种基于高斯的粗粒度电子结构模型，它同时捕获多体极化和色散，并且具有随系统规模线性变化的计算复杂性，因此是一种领先的下一代模拟方法。在这里，我们调查QDO处理在多大程度上再现了所需的远程原子和分子性质。我们给出了前导阶极化率和色散系数的封闭表达式，并导出了由于模型的高斯性质而产生的多极极化率和多体色散系数之间的不变(无参数)标度关系。我们发现，对于稀有气体原子、碱金属和简单的(第一排氢化物)分子，如水，这些“组合规则”保持在几个百分点以内；这与在物理学中使用潜在的高斯统计的模型经常展示的惊人的成功是一致的。我们提出了一个图解的Jastrow-type微扰理论，该理论是为QDO模型量身定做的，用于说明QDO方法产生的丰富类型的响应。通过线性尺度扩散蒙特卡罗(DMC)和路径积分分子动力学(PIMD)模拟，建立了用于再现气相性质的Ne、Ar、氪和氙气的QDO模型，并研究了它们的凝聚相性质。在结构、结合能和体弹性模量方面与实验数据有很好的一致性，证明了一定程度的可转移性，这是目前的经验模型或完全从头算描述所不能实现的。DOI：10.1103/PhysRevB.87.144103
Treating both many-body polarization and dispersion interactions is now recognized as a key element in achieving the level of atomistic modeling required to reveal novel physics in complex systems. The quantum Drude oscillator (QDO), a Gaussian-based, coarse grained electronic structure model, captures both many-body polarization and dispersion and has linear scale computational complexity with system size, hence it is a leading candidate next-generation simulation method. Here, we investigate the extent to which the QDO treatment reproduces the desired long-range atomic and molecular properties. We present closed form expressions for leading order polarizabilities and dispersion coefficients and derive invariant (parameter-free) scaling relationships among multipole polarizability and many-body dispersion coefficients that arise due to the Gaussian nature of the model. We show that these "combining rules" hold to within a few percent for noble gas atoms, alkali metals, and simple (first-row hydride) molecules such as water; this is consistent with the surprising success that models with underlying Gaussian statistics often exhibit in physics. We present a diagrammatic Jastrow-type perturbation theory tailored to the QDO model that serves to illustrate the rich types of responses that the QDO approach engenders. QDO models for neon, argon, krypton, and xenon, designed to reproduce gas phase properties, are constructed and their condensed phase properties explored via linear scale diffusion Monte Carlo (DMC) and path integral molecular dynamics (PIMD) simulations. Good agreement with experimental data for structure, cohesive energy, and bulk modulus is found, demonstrating a degree of transferability that cannot be achieved using current empirical models or fully ab initio descriptions. DOI: 10.1103/PhysRevB.87.144103