Wilhelm Jan, Golze Dorothea, Talirz Leopold, Hutter Jürg, Pignedoli Carlo A
Department of Chemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
COMP/Department of Applied Physics, Aalto University , P.O. Box 11100, FI-00076 Aalto, Finland.
J Phys Chem Lett. 2018 Jan 18;9(2):306-312. doi: 10.1021/acs.jpclett.7b02740. Epub 2018 Jan 5.
The GW approximation of many-body perturbation theory is an accurate method for computing electron addition and removal energies of molecules and solids. In a canonical implementation, however, its computational cost is [Formula: see text] in the system size N, which prohibits its application to many systems of interest. We present a full-frequency GW algorithm in a Gaussian-type basis, whose computational cost scales with N to N. The implementation is optimized for massively parallel execution on state-of-the-art supercomputers and is suitable for nanostructures and molecules in the gas, liquid or condensed phase, using either pseudopotentials or all electrons. We validate the accuracy of the algorithm on the GW100 molecular test set, finding mean absolute deviations of 35 meV for ionization potentials and 27 meV for electron affinities. Furthermore, we study the length-dependence of quasiparticle energies in armchair graphene nanoribbons of up to 1734 atoms in size, and compute the local density of states across a nanoscale heterojunction.
多体微扰理论的GW近似是一种计算分子和固体的电子添加和去除能量的精确方法。然而，在传统的实现方式中，其计算成本与系统大小N呈[公式：见原文]关系，这限制了它在许多感兴趣的系统中的应用。我们提出了一种基于高斯型基的全频GW算法，其计算成本与N呈N的比例关系。该实现针对在最先进的超级计算机上进行大规模并行执行进行了优化，适用于气体、液体或凝聚相中的纳米结构和分子，可使用赝势或全电子。我们在GW100分子测试集上验证了该算法的准确性，发现电离势的平均绝对偏差为35毫电子伏特，电子亲和势的平均绝对偏差为27毫电子伏特。此外，我们研究了尺寸达1734个原子的扶手椅型石墨烯纳米带中的准粒子能量的长度依赖性，并计算了纳米级异质结上的局域态密度。
