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Extrapolation to the Limit of a Complete Pair Natural Orbital Space in Local Coupled-Cluster Calculations
[Image: see text] The domain-based local pair natural orbital (PNO) coupled-cluster DLPNO-CCSD(T) method allows one to perform single point energy calculations for systems with hundreds of atoms while retaining essentially the accuracy of its canonical counterpart, with errors that are typically sma...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American
Chemical Society
2020
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7586325/ https://www.ncbi.nlm.nih.gov/pubmed/32897712 http://dx.doi.org/10.1021/acs.jctc.0c00344 |
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author | Altun, Ahmet Neese, Frank Bistoni, Giovanni |
author_facet | Altun, Ahmet Neese, Frank Bistoni, Giovanni |
author_sort | Altun, Ahmet |
collection | PubMed |
description | [Image: see text] The domain-based local pair natural orbital (PNO) coupled-cluster DLPNO-CCSD(T) method allows one to perform single point energy calculations for systems with hundreds of atoms while retaining essentially the accuracy of its canonical counterpart, with errors that are typically smaller than 1 kcal/mol for relative energies. Crucial to the accuracy and efficiency of the method is a proper definition of the virtual space in which the coupled-cluster equations are solved, which is spanned by a highly compact set of pair natural orbitals (PNOs) that are specific for each electron pair. The dimension of the PNO space is controlled by the T(CutPNO) threshold: only PNOs with an occupation number greater than T(CutPNO) are included in the correlation space of a given electron pair, whilst the remaining PNOs are discarded. To keep the error of the method small, a conservative T(CutPNO) value is used in standard DLPNO-CCSD(T) calculations. This often leads to unnecessarily large PNO spaces, which limits the efficiency of the method. Herein, we introduce a new computational strategy to approach the complete PNO space limit (for a given basis set) that consists in extrapolating the results obtained with different T(CutPNO) values. The method is validated on the GMTKN55 set using canonical CCSD(T) data as the reference. Our results demonstrate that a simple two-point extrapolation scheme can be used to significantly increase the efficiency and accuracy of DLPNO-CCSD(T) calculations, thus extending the range of applicability of the technique. |
format | Online Article Text |
id | pubmed-7586325 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | American
Chemical Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-75863252020-10-27 Extrapolation to the Limit of a Complete Pair Natural Orbital Space in Local Coupled-Cluster Calculations Altun, Ahmet Neese, Frank Bistoni, Giovanni J Chem Theory Comput [Image: see text] The domain-based local pair natural orbital (PNO) coupled-cluster DLPNO-CCSD(T) method allows one to perform single point energy calculations for systems with hundreds of atoms while retaining essentially the accuracy of its canonical counterpart, with errors that are typically smaller than 1 kcal/mol for relative energies. Crucial to the accuracy and efficiency of the method is a proper definition of the virtual space in which the coupled-cluster equations are solved, which is spanned by a highly compact set of pair natural orbitals (PNOs) that are specific for each electron pair. The dimension of the PNO space is controlled by the T(CutPNO) threshold: only PNOs with an occupation number greater than T(CutPNO) are included in the correlation space of a given electron pair, whilst the remaining PNOs are discarded. To keep the error of the method small, a conservative T(CutPNO) value is used in standard DLPNO-CCSD(T) calculations. This often leads to unnecessarily large PNO spaces, which limits the efficiency of the method. Herein, we introduce a new computational strategy to approach the complete PNO space limit (for a given basis set) that consists in extrapolating the results obtained with different T(CutPNO) values. The method is validated on the GMTKN55 set using canonical CCSD(T) data as the reference. Our results demonstrate that a simple two-point extrapolation scheme can be used to significantly increase the efficiency and accuracy of DLPNO-CCSD(T) calculations, thus extending the range of applicability of the technique. American Chemical Society 2020-09-08 2020-10-13 /pmc/articles/PMC7586325/ /pubmed/32897712 http://dx.doi.org/10.1021/acs.jctc.0c00344 Text en This is an open access article published under a Creative Commons Attribution (CC-BY) License (http://pubs.acs.org/page/policy/authorchoice_ccby_termsofuse.html) , which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. |
spellingShingle | Altun, Ahmet Neese, Frank Bistoni, Giovanni Extrapolation to the Limit of a Complete Pair Natural Orbital Space in Local Coupled-Cluster Calculations |
title | Extrapolation to the Limit of a Complete Pair Natural
Orbital Space in Local Coupled-Cluster Calculations |
title_full | Extrapolation to the Limit of a Complete Pair Natural
Orbital Space in Local Coupled-Cluster Calculations |
title_fullStr | Extrapolation to the Limit of a Complete Pair Natural
Orbital Space in Local Coupled-Cluster Calculations |
title_full_unstemmed | Extrapolation to the Limit of a Complete Pair Natural
Orbital Space in Local Coupled-Cluster Calculations |
title_short | Extrapolation to the Limit of a Complete Pair Natural
Orbital Space in Local Coupled-Cluster Calculations |
title_sort | extrapolation to the limit of a complete pair natural
orbital space in local coupled-cluster calculations |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7586325/ https://www.ncbi.nlm.nih.gov/pubmed/32897712 http://dx.doi.org/10.1021/acs.jctc.0c00344 |
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