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Communication: An N-body solution to the problem of Fock exchange
Matt Challacombe1, Nicolas Bock1
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Abstract:
We report an N-Body approach to computing the Fock exchange matrix with and without permutational symmetry. The method achieves an O(NlgN) computational complexity through an embedded metric-query, allowing hierarchical application of direct SCF criteria. The advantages of permutational symmetry are found to be 4-fold for small systems, but decreasing with increasing system size and/or more permissive neglect criteria. This work sets the stage for: (1) the introduction of range queries in multi-level multipole schemes for rank reduction, and (2) recursive task parallelism.
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