Large-scale ab initio simulations based on systematically improvable atomic basis

We present a first-principles computer code package (ABACUS) that is based on density functional theory and numerical atomic basis sets. Theoretical foundations and numerical techniques used in the code are described, with focus on the accuracy and transferability of the hierarchical atomic basis sets as generated using a scheme proposed by Chen et al. (2010). Benchmark results are presented for a variety of systems include molecules, solids, surfaces, and defects. All results show that the ABACUS package with its associated atomic basis sets is an efficient and reliable tool for simulating both small and large-scale materials.

The scaling behavior of ABACUS code on the computational time of one electronic iteration of bulk Si (diamond structure) as a function of the system size. We use eight supercells containing 8, 64, 128, 192, 256, 384, 512, and 768 atoms respectively. For all calculations 8 Intel(R) Xeon(R) CPU cores were used. Figure optionsDownload as PowerPoint slide