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A near linear-scaling smooth local coupled cluster algorithm for electronic structure.

Joseph E Subotnik·Alex Sodt·Martin Head-Gordon
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Abstract

We demonstrate near linear scaling of a new algorithm for computing smooth local coupled-cluster singles-doubles (LCCSD) correlation energies of quantum mechanical systems. The theory behind our approach has been described previously, [J. Subotnik and M. Head-Gordon, J. Chem. Phys. 123, 064108 (2005)], and requires appropriately multiplying standard iterative amplitude equations by a bump function, creating local amplitude equations (which are smooth according to the implicit function theorem). Here, we provide an example that this theory works in practice: we show that our algorithm leads to smooth potential energy surfaces and yields large computational savings. As an example, we apply our LCCSD approach to measure the post-MP2 correction to the energetic gap between two different alanine tetrapeptide conformations.

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AlgorithmsChemical PhenomenaChemistry, PhysicalComputer SimulationModels, ChemicalJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Joseph E Subotnik, Alex Sodt, Martin Head-Gordon. 2006-08-21. A near linear-scaling smooth local coupled cluster algorithm for electronic structure.. https://doi.org/10.1063/1.2336426

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