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Improvements on the direct SCF method

✍ Scribed by Marco Häser; Reinhart Ahlrichs

Publisher
John Wiley and Sons
Year
1989
Tongue
English
Weight
643 KB
Volume
10
Category
Article
ISSN
0192-8651

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✦ Synopsis

Three improvements on the direct self-consistent field method are proposed and tested which together increase CPU-efficiency by about 50%: (i) selective storage of costly integral batches; (ii) improved integral bond for prescreening; (iii) decomposition of the current density matrix into a linear combination of previous density matricesfor which the two-electron contributions to the Fock matrix are availableand a remainder AD, which is minimized; construction of the current Fock matrix only requires processing of the small AD which enhances prescreening.

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