New pecJ-n (n = 1, 2) Basis Sets for High-Quality Calculations of Indirect Nuclear Spin–Spin Coupling Constants Involving 31P and 29Si: The Advanced PEC Method

Abstract

In this paper, we presented new J-oriented basis sets, pecJ-n (n = 1, 2), for phosphorus and silicon, purposed for the high-quality correlated calculations of the NMR spin–spin coupling constants involving these nuclei. The pecJ-n basis sets were generated using the modified version of the property-energy consistent (PEC) method, which was introduced in our earlier paper. The modifications applied to the original PEC procedure increased the overall accuracy and robustness of the generated basis sets in relation to the diversity of electronic systems. Our new basis sets were successfully tested on a great number of spin–spin coupling constants, involving phosphorus or/and silicon, calculated within the SOPPA(CCSD) method. In general, it was found that our new pecJ-1 and pecJ-2 basis sets are very efficient, providing the overall accuracy that can be characterized by MAEs of about 3.80 and 1.98 Hz, respectively, against the benchmark data obtained with a large dyall.aae4z+ basis set of quadruple-ζ quality.

New pecJ-n (n = 1, 2) Basis Sets for Selenium Atom Purposed for the Calculations of NMR Spin–Spin Coupling Constants Involving Selenium

“…In the end, only one set is selected-the one that provides the property value within the desired range and the lowest energy. For the detailed description of the PEC algorithm and its peculiarities as applied to the generation of the J-oriented basis sets, we refer the reader to our earlier works presenting the basics of the method [98,99]. Although, it should be mentioned that the PEC method is unique in the sense of dealing with two target functions (the property and the energy) simultaneously.…”

“…In this paper, we present new compact J-oriented basis sets for the selenium atom that have been obtained within the property-energy consistent (PEC) method, introduced in our previous studies [98][99][100]. The PEC method is based on the consistent optimization of all exponents using the Monte Carlo (MC) simulations [101][102][103], with respect to the property under consideration and the total molecular energy.…”

On the Utmost Importance of the Basis Set Choice for the Calculations of the Relativistic Corrections to NMR Shielding Constants

“…In the nonrelativistic level of theory, many efforts have been made to develop efficient specialized basis sets for NMR properties in order to decrease the computational costs of their quantum-chemical calculations. In particular, there were many specialized basis sets introduced for spin-spin coupling constants ( J -oriented basis sets) [ 52 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 ] and, to a lesser extent, for chemical shifts or shielding constants (σ-oriented basis sets) [ 51 , 74 , 75 , 76 ]. At the same time, for the relativistic level of theory, the issue of specialized basis sets for NMR parameters still remains open.…”

New efficient pecS-n (n = 1, 2) basis sets for quantum chemical calculations of 31P NMR chemical shifts

“…The exponents and contraction coefficients were generated with the property-energy consistent (PEC) method that has been introduced in our earlier paper 35 and was successfully applied to obtain chemical shift-and spin-spin coupling constant-oriented basis sets for some NMR-active nuclei of 1-4 periods. [35][36][37][38] The PEC algorithm is based on the consistent optimization of all exponents using Monte Carlo simulations with respect to the property under consideration and the total molecular energy. This gives very efficient property-oriented basis sets, capable of providing the accuracy close to that reached at with noticeably larger basis sets.…”