An efficient self-consistent field method for large systems of weakly interacting components
An efficient self-consistent field method for large systems of weakly interacting components
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DOI：
10.1063/1.2191500
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发表时间：
2006-05-28
影响因子：
4.4
通讯作者：
Bell, Alexis T.
中科院分区：
文献类型：
--
作者：
Khaliullin, Rustam Z.;Head-Gordon, Martin;Bell, Alexis T.
针对弱相互作用系统，提出了一种消除自洽场对角化瓶颈的有效方法。该方法是基于局部投影SCF分子相互作用（SCF MI），利用绝对本地化的非正交分子轨道在原子基组的局部子集扩展的方程。为了提高SCF MI方程的收敛速度，在迭代子空间中推广了非正交分子轨道的直接反演。为了提高SCF MI能量的准确性，我们发展了单步Roothaan微扰修正。由此产生的能量密切再现传统的SCF能量。广泛的测试计算进行水簇多达几百个分子。与传统SCF相比，对角化步骤已经实现了（N/O）（2）数量级的加速，其中N是原子轨道基的大小，O是占据的分子轨道的数目。(c)2006年，美国物理学会。
An efficient method for removing the self-consistent field (SCF) diagonalization bottleneck is proposed for systems of weakly interacting components. The method is based on the equations of the locally projected SCF for molecular interactions (SCF MI) which utilize absolutely localized nonorthogonal molecular orbitals expanded in local subsets of the atomic basis set. A generalization of direct inversion in the iterative subspace for nonorthogonal molecular orbitals is formulated to increase the rate of convergence of the SCF MI equations. Single Roothaan step perturbative corrections are developed to improve the accuracy of the SCF MI energies. The resulting energies closely reproduce the conventional SCF energy. Extensive test calculations are performed on water clusters up to several hundred molecules. Compared to conventional SCF, speedups of the order of (N/O)(2) have been achieved for the diagonalization step, where N is the size of the atomic orbital basis, and O is the number of occupied molecular orbitals. (c) 2006 American Institute of Physics.