论文标题
有效的DFT求解器，用于纳米级模拟及其他
An Efficient DFT Solver for Nanoscale Simulations and Beyond
论文作者
论文摘要
我们提出了单轨集合自洽场（OE-SCF）方法，一种{替代}无轨道DFT求解器，该方法将DFT扩展到纳米级以外的系统大小的适用性，同时保留所需的准确性。 OE-SCF是一种迭代求解器，其中（通常在计算上昂贵的）Pauli电位被视为外部电位，并在每次迭代后进行更新。由于仅需要多达十几次迭代才能达到收敛，因此OE-SCF极大地超过了当前无轨道的DFT求解器。我们仅采用单个CPU，对迄今为止的基于硅的材料进行了最大的AB从头算模拟。 OE-SCF能够收集大量切割的Si纳米颗粒的能量，这是其直径的函数，最高为16 nm，这是首次再现已知的经验结果。当将Si平板夹在两个金属平板之间时，我们对极化和界面电荷传递进行了建模，晶格匹配的板尺寸很大。此外，OE-SCF还为在无轨道的DFT模拟中采用更准确的功能打开了大门，同时仍在处理纳米级以外的系统尺寸。
We present the One-orbital Ensemble Self-Consistent Field (OE-SCF) method, an {alternative} orbital-free DFT solver that extends the applicability of DFT to system sizes beyond the nanoscale while retaining the accuracy required to be predictive. OE-SCF is an iterative solver where the (typically computationally expensive) Pauli potential is treated as an external potential and updated after each iteration. Because only up to a dozen iterations are needed to reach convergence, OE-SCF dramatically outperforms current orbital-free DFT solvers. Employing merely a single CPU, we carried out the largest ab initio simulation for silicon-based materials to date. OE-SCF is able to converge the energy of bulk-cut Si nanoparticles as a function of their diameter up to 16 nm, for the first time reproducing known empirical results. We model polarization and interface charge transfer when a Si slab is sandwiched between two metal slabs where lattice matching mandates a very large slab size. Additionally, OE-SCF opens the door to adopt even more accurate functionals in orbital-free DFT simulations while still tackling systems sizes beyond the nanoscale.
