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Avoiding Negligible Shell Pairs and Quartets in Electronic Structure Calculations.

ABSTRACT: We define a significant shell pair in an electronic structure calculation as one that generates at least one two-electron integral larger than a preset threshold. We define a significant shell quartet similarly. We then explore several methods for identifying nonsignificant pairs and quartets so that they can be avoided and computational efficiency improved. We find that the widely used Cauchy-Schwarz bound identifies most nonsignificant quartets but that the Hölder bound is slightly more powerful for identifying nonsignificant pairs.

SUBMITTER: Black EKG

PROVIDER: S-EPMC9885959 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Avoiding Negligible Shell Pairs and Quartets in Electronic Structure Calculations.

Black Ellena K G EKG Gilbert Andrew T B ATB McKenzie Simon C SC Gill Peter M W PMW

The journal of physical chemistry. A 20230117 3

We define a significant shell pair in an electronic structure calculation as one that generates at least one two-electron integral larger than a preset threshold. We define a significant shell quartet similarly. We then explore several methods for identifying nonsignificant pairs and quartets so that they can be avoided and computational efficiency improved. We find that the widely used Cauchy-Schwarz bound identifies most nonsignificant quartets but that the Hölder bound is slightly more powerf ...[more]

PMID: 36649286

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