Department of Physics, Imperial College London, Exhibition Road, SW7 2AZ London, United Kingdom.
J Chem Phys. 2010 Sep 21;133(11):114111. doi: 10.1063/1.3492379.
We present calculations of formation energies of defects in an ionic solid (Al(2)O(3)) extrapolated to the dilute limit, corresponding to a simulation cell of infinite size. The large-scale calculations required for this extrapolation are enabled by developments in the approach to parallel sparse matrix algebra operations, which are central to linear-scaling density-functional theory calculations. The computational cost of manipulating sparse matrices, whose sizes are determined by the large number of basis functions present, is greatly improved with this new approach. We present details of the sparse algebra scheme implemented in the ONETEP code using hierarchical sparsity patterns, and demonstrate its use in calculations on a wide range of systems, involving thousands of atoms on hundreds to thousands of parallel processes.
我们给出了在稀极限下(对应于无限大的模拟胞)离子固体(Al2O3)中缺陷形成能的计算结果。这种外推需要进行大规模的计算,而这得益于并行稀疏矩阵代数运算方法的发展,该方法是线性标度密度泛函理论计算的核心。通过这种新方法,可以大大提高处理稀疏矩阵的计算成本,稀疏矩阵的大小由存在的大量基函数决定。我们给出了在 ONETEP 代码中使用分层稀疏模式实现的稀疏代数方案的详细信息,并展示了其在广泛的系统计算中的应用,涉及到数百到数千个并行进程上的数千个原子。