Parallel implementation of a mesh-based density functional electronic structure code

✍ Scribed by Y. S. Li; M. C. Wrinn; J. M. Newsam; M. P. Sears

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 807 KB
• Volume: 16
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.540160209

✦ Synopsis

We describe the implementation of the mesh-based first-principles density functional code DMol on nCUBE 2 parallel computers. The numerical mesh nature of DMol makes it naturally suited for a massively parallel computational environment. Our parallelization strategy consists of a domain decomposition of mesh points. This evenly distributes mesh points to all available processors and leads to a substantial computational speedup with limited communication overhead and good node balancing. To achieve better performance and circumvent memory storage limitations, the torus wrap method is used to distribute both the Hamiltonian and overlap matrices, and a parallel matrix diagonalization routine is employed to calculate eigenvalues and eigenvectors. Benchmark calculations on a 128-node nCUBE 2 are presented. Wiley & Sons, Inc. 0 1995 by John properties of molecules, clusters, solids, and surfaces,',' Compared to traditional quantum chemistry methods (such as Hartree-Fock), density functional theory in the local density approximation (LDA)3,4 offers computational advantages due to its approximately third-power dependence on the number of atoms and basis orbital^.^ It is also reasonably accurate because electron correlation is included in the formalism. Such calculations are still computationally intensive and require sub-*Author to whom all correspondence should be addressed.