{"title":"SDSPT2s:SDSPT2 with Selection.","authors":"Yibo Lei, Yang Guo, Bingbing Suo, Wenjian Liu","doi":"10.1021/acs.jctc.4c01596","DOIUrl":null,"url":null,"abstract":"<p><p>As an approximation to SDSCI [static-dynamic-static (SDS) configuration interaction (CI), a minimal MRCI; <i>Theor. Chem. Acc.</i> <b>2014</b>, <i>133</i>, 1481], SDSPT2 [<i>Mol. Phys.</i> <b>2017</b>, <i>115</i>, 2696] is a CI-like multireference (MR) second-order perturbation theory (PT2) that treats single and multiple roots in the same manner. This feature permits the use of configuration selection over a large complete active space (CAS) <i>P</i> to end up with a much reduced reference space <i>P</i>̃, which is connected only with a small portion (<i>Q</i>̃<sub>1</sub>) of the full first-order interacting space <i>Q</i> connected to <i>P</i>. The most expensive portion of the reduced interacting <i>Q</i>̃<sub>1</sub> space (which involves three active orbitals) can further be truncated by partially bypassing its generation followed by an integral-based cutoff. With marginal loss of accuracy, the selection-truncation procedure, along with an efficient evaluation and storage of internal contraction coefficients, renders SDSPT2s (SDSPT2 with selection) applicable to systems that cannot be handled by the parent CAS-based SDSPT2, as demonstrated by several challenging showcases.</p>","PeriodicalId":45,"journal":{"name":"Journal of Chemical Theory and Computation","volume":" ","pages":"1259-1275"},"PeriodicalIF":5.7000,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Chemical Theory and Computation","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.jctc.4c01596","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/1/23 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
As an approximation to SDSCI [static-dynamic-static (SDS) configuration interaction (CI), a minimal MRCI; Theor. Chem. Acc.2014, 133, 1481], SDSPT2 [Mol. Phys.2017, 115, 2696] is a CI-like multireference (MR) second-order perturbation theory (PT2) that treats single and multiple roots in the same manner. This feature permits the use of configuration selection over a large complete active space (CAS) P to end up with a much reduced reference space P̃, which is connected only with a small portion (Q̃1) of the full first-order interacting space Q connected to P. The most expensive portion of the reduced interacting Q̃1 space (which involves three active orbitals) can further be truncated by partially bypassing its generation followed by an integral-based cutoff. With marginal loss of accuracy, the selection-truncation procedure, along with an efficient evaluation and storage of internal contraction coefficients, renders SDSPT2s (SDSPT2 with selection) applicable to systems that cannot be handled by the parent CAS-based SDSPT2, as demonstrated by several challenging showcases.
期刊介绍:
The Journal of Chemical Theory and Computation invites new and original contributions with the understanding that, if accepted, they will not be published elsewhere. Papers reporting new theories, methodology, and/or important applications in quantum electronic structure, molecular dynamics, and statistical mechanics are appropriate for submission to this Journal. Specific topics include advances in or applications of ab initio quantum mechanics, density functional theory, design and properties of new materials, surface science, Monte Carlo simulations, solvation models, QM/MM calculations, biomolecular structure prediction, and molecular dynamics in the broadest sense including gas-phase dynamics, ab initio dynamics, biomolecular dynamics, and protein folding. The Journal does not consider papers that are straightforward applications of known methods including DFT and molecular dynamics. The Journal favors submissions that include advances in theory or methodology with applications to compelling problems.