论文标题
低规模的$ GW $具有基准精度和磷纳米片的应用
Low-scaling $GW$ with benchmark accuracy and application to phosphorene nanosheets
论文作者
论文摘要
$ GW $是计算分子和固体的电子添加和去除能的准确方法。但是，在传统的$ GW $实施中，其计算成本为系统尺寸$ n $的$ O（n^4）$，这禁止其应用于许多感兴趣的系统。与我们以前的算法相比，我们提出了一种低标准的$ GW $算法，其精度明显提高[J.物理。化学Lett。 2018，9，306-312]。使用$ GW100 $基准组的边界轨道证明了这一点，我们的算法在该算法中仅相对于规范实现了6 MEV的平均绝对偏差。我们表明，在0.1 eV中，深度价，半核和未结合状态的激发与常规方案相匹配。通过使用具有30个网格点的最小网格，并用截短的库仑度量分辨出身份，可以实现高精度。我们将低标准的$ GW $算法应用于增加尺寸的磷光纳米片的精度。我们发现，它们的基本差距大小依赖性，从4.0 eV（1.8 nm $ \ times $ 1.3 nm，88原子）到2.4 eV（6.9 nm $ \ times $ 4.8 nm，990原子，990个原子），在$ \ text {ev ev} gw_0 $@pbe水平。
$GW$ is an accurate method for computing electron addition and removal energies of molecules and solids. In a conventional $GW$ implementation, however, its computational cost is $O(N^4)$ in the system size $N$, which prohibits its application to many systems of interest. We present a low-scaling $GW$ algorithm with notably improved accuracy compared to our previous algorithm [J. Phys. Chem. Lett. 2018, 9, 306-312]. This is demonstrated for frontier orbitals using the $GW100$ benchmark set, for which our algorithm yields a mean absolute deviation of only 6 meV with respect to canonical implementations. We show that also excitations of deep valence, semi-core and unbound states match conventional schemes within 0.1 eV. The high accuracy is achieved by using minimax grids with 30 grid points and the resolution of the identity with the truncated Coulomb metric. We apply the low-scaling $GW$ algorithm with improved accuracy to phosphorene nanosheets of increasing size. We find that their fundamental gap is strongly size-dependent varying from 4.0 eV (1.8 nm $\times$ 1.3 nm, 88 atoms) to 2.4 eV (6.9 nm $\times$ 4.8 nm, 990 atoms) at the $\text{ev}GW_0$@PBE level.
