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arXiv · 1401.6961

An N-Body Solution to the Problem of Fock Exchange

Matt Challacombe·Nicolas Bock
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Abstract

We report an N-Body approach to computing the Fock exchange matrix with and without permutational symmetry. The method achieves an O(N lg N) 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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Matt Challacombe, Nicolas Bock. 2014-01-27. An N-Body Solution to the Problem of Fock Exchange. https://doi.org/10.1063/1.4868636

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