ELSI: A unified software interface for KohnSham electronic structure solvers
Abstract
Solving the electronic structure from a generalized or standard eigenproblem is often the bottleneck in large scale calculations based on KohnSham densityfunctional theory. This problem must be addressed by essentially all current electronic structure codes, based on similar matrix expressions, and by highperformance computation. We here present a unified software interface, ELSI, to access different strategies that address the KohnSham eigenvalue problem. Currently supported algorithms include the dense generalized eigensolver library ELPA, the orbital minimization method implemented in libOMM, and the pole expansion and selected inversion (PEXSI) approach with lower computational complexity for semilocal density functionals. The ELSI interface aims to simplify the implementation and optimal use of the different strategies, by offering (a) a unified software framework designed for the electronic structure solvers in KohnSham densityfunctional theory; (b) reasonable default parameters for a chosen solver; (c) automatic conversion between input and internal working matrix formats, and in the future (d) recommendation of the optimal solver depending on the specific problem. Comparative benchmarks are shown for system sizes up to 11,520 atoms (172,800 basis functions) on distributed memory supercomputing architectures.
 Publication:

Computer Physics Communications
 Pub Date:
 January 2018
 DOI:
 10.1016/j.cpc.2017.09.007
 arXiv:
 arXiv:1705.11191
 Bibcode:
 2018CoPhC.222..267Y
 Keywords:

 Densityfunctional theory;
 KohnSham eigenvalue problem;
 Parallel computing;
 Physics  Computational Physics;
 Condensed Matter  Materials Science
 EPrint:
 55 pages, 14 figures, 2 tables