1. RPA(D) and HRPA(D): Two new models for calculations of NMR indirect nuclear spin–spin coupling constants.
- Author
-
Schnack‐Petersen, Anna Kristina, Haase, Pi A. B., Faber, Rasmus, Provasi, Patricio F., and Sauer, Stephan P. A.
- Subjects
- *
NUCLEAR spin , *NUCLEAR magnetic resonance , *SPIN-spin interactions , *MATHEMATICAL models , *DISCRETIZATION methods - Abstract
In this article, the RPA(D) and HRPA(D) models for the calculation of linear response functions are presented. The performance of the new RPA(D) and HRPA(D) models is compared to the performance of the established RPA, HRPA, and SOPPA models in calculations of indirect nuclear spin–spin coupling constants using the CCSD model as a reference. The doubles correction offers a significant improvement on both the RPA and HRPA models; however, the improvement is more dramatic in the case of the RPA model. For all coupling types investigated in this study, the results obtained using the HRPA(D) model are comparable in accuracy to those given by the SOPPA model, while requiring between 30% and 90% of the calculation time needed for SOPPA. The RPA(D) model, while of slightly lower accuracy compared to the CCSD model than HRPA(D), offered calculation times of only approximately 25% of those required for SOPPA for all the investigated molecules. © 2018 Wiley Periodicals, Inc. Two new models have been introduced for the calculation of indirect nuclear spin–spin coupling constants. The two new models perform well compared to the computationally more expensive SOPPA model, with the HRPA(D) model performing with almost the same accuracy as the SOPPA model. The RPA(D) model also gives results of good accuracy compared to the SOPPA model and in addition also offers a substantial reduction of the calculation time. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF