Electronic-structure calculations and molecular-dynamics simulations with linear system-size scaling.
Electronic-structure calculations and molecular-dynamics simulations with linear system-size scaling.
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具有线性系统尺寸缩放的电子结构计算和分子动力学模拟。
DOI：
10.1103/physrevb.50.4316
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Galli
中科院分区：
文献类型：
--
作者：
Mauri;Galli
我们提出了一种基于紧束缚或Kohn-Sham哈密顿量的总能量最小化和分子动力学模拟方法。该方法导致一个算法，其计算成本与系统规模呈线性关系。我们的方法的主要特点是：（i）一个轨道公式与单粒子波函数被限制在特定区域的空间，和（ii）能量泛函，不需要显式正交化的电子轨道，或反转的重叠矩阵。讨论了该方法的基础和精度以及算法的性能，并通过包括Kohn-Sham哈密顿算子在内的几个数值例子进行了说明。特别是，我们目前的计算与紧束缚哈密顿金刚石，石墨，碳线性链，和液体碳在低压下。即使对于一个复杂的情况，如液态碳22 {}，一个无序的金属系统与不同的协调原子22 {}之间的协议标准对角化方案和我们的方法是非常好的。我们的研究结果建立了广泛的一类系统的方法的准确性和可靠性，并表明，紧束缚分子动力学模拟与几千个原子在小型工作站上是可行的。
We present a method for total-energy minimizations and molecular-dynamics simulations based either on tight-binding or on Kohn-Sham Hamiltonians. The method leads to an algorithm whose computational cost scales linearly with the system size. The key features of our approach are (i) an orbital formulation with single-particle wave functions constrained to be localized in given regions of space, and (ii) an energy functional that does not require either explicit orthogonalization of the electronic orbitals, or inversion of an overlap matrix. The foundations and accuracy of the approach and the performances of the algorithm are discussed, and illustrated with several numerical examples including Kohn-Sham Hamiltonians. In particular, we present calculations with tight-binding Hamiltonians for diamond, graphite, a carbon linear chain, and liquid carbon at low pressure. Even for a complex case such as liquid carbon\char22{}a disordered metallic system with differently coordinated atoms\char22{}the agreement between standard diagonalization schemes and our approach is very good. Our results establish the accuracy and reliability of the method for a wide class of systems and show that tight-binding molecular-dynamics simulations with a few thousand atoms are feasible on small workstations.