A variational linear-scaling framework to build practical, efficient next-generation orbital-based quantum force fields.
A variational linear-scaling framework to build practical, efficient next-generation orbital-based quantum force fields.
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DOI：
10.1021/ct3010134
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发表时间：
2013-03-12
影响因子：
5.5
通讯作者：
York, Darrin M.
中科院分区：
文献类型：
--
作者：
Giese, Timothy J.;Chen, Haoyuan;Dissanayake, Thakshila;Giambasu, George M.;Heldenbrand, Hugh;Huang, Ming;Kuechler, Erich R.;Lee, Tai-Sung;Panteva, Maria T.;Radak, Brian K.;York, Darrin M.
我们介绍了一种新的混合分子轨道/密度泛函修改分而治之（mDC）的方法，允许非常大的量子系统的线性标度计算。该方法提供了一个强大的框架，从线性尺度力场的分子模拟可以开发。该方法是变分的能量，并具有简单的，解析梯度和基本上没有盈亏平衡点相对于相应的全电子结构计算。此外，新的方法允许分子间力被适当地平衡，使得在某些情况下，非键相互作用可以被处理到比完整计算高得多的精度。使用二阶自洽电荷密度泛函紧束缚模型（DFTB 2）的方法来说明。使用该模型作为基础哈密顿量，新的mDC方法被应用到一系列的水系统，结果表明，水分子之间的几何形状和相互作用能大大改善相对于全DFTB 2。为了实现大幅度提高分子间结合能和氢键团簇几何形状的准确性，有必要将DFTB 2模型扩展到高阶原子中心多极子，以获得二阶自洽分子间静电项。使用广义的，线性尺度的静电方法，计时表明，该方法能够计算一个水系统的3000个原子在不到半秒的时间，和系统的多达一百万个原子在短短几分钟内使用传统的桌面工作站。
We introduce a new hybrid molecular orbital/density-functional modified divide-and-conquer (mDC) approach that allows the linear-scaling calculation of very large quantum systems. The method provides a powerful framework from which linear-scaling force fields for molecular simulations can be developed. The method is variational in the energy, and has simple, analytic gradients and essentially no break-even point with respect to the corresponding full electronic structure calculation. Furthermore, the new approach allows intermolecular forces to be properly balanced such that non-bonded interactions can be treated, in some cases, to much higher accuracy than the full calculation. The approach is illustrated using the second-order self-consistent charge density-functional tight-binding model (DFTB2). Using this model as a base Hamiltonian, the new mDC approach is applied to a series of water systems, where results show that geometries and interaction energies between water molecules are greatly improved relative to full DFTB2. In order to achieve substantial improvement in the accuracy of intermolecular binding energies and hydrogen bonded cluster geometries, it was necessary to extend the DFTB2 model to higher-order atom-centered multipoles for the second-order self-consistent intermolecular electrostatic term. Using generalized, linear-scaling electrostatic methods, timings demonstrate that the method is able to calculate a water system of 3000 atoms in less than half of a second, and systems of up to one million atoms in only a few minutes using a conventional desktop workstation.
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影响因子：
4.4
作者：
Cisneros, G. Andres;Piquemal, Jean-Philip;Darden, Thomas A.
通讯作者：
Darden, Thomas A.
影响因子：
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作者：
Cisneros, G. Andres;Elking, Dennis;Darden, Thomas A.
通讯作者：
Darden, Thomas A.
影响因子：
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作者：
Cembran, Alessandro;Bao, Peng;Wang, Yingjie;Song, Lingchun;Truhlar, Donald G.;Gao, Jiali
通讯作者：
Gao, Jiali
影响因子：
5.5
作者：
Elliott, Peter;Cohen, Morrel H.;Burke, Kieron
通讯作者：
Burke, Kieron
影响因子：
4.4
作者：
Challacombe, M
通讯作者：
Challacombe, M