title: Convergence of Nuclear Magnetic Shieldings in the Kohn-Sham Limit for Several Small Molecules.
abstract: Convergence patterns and limiting values of isotropic nuclear magnetic shieldings were studied for several small molecules (N2, CO, CO2, NH3, CH4, C2H2, C2H4, C2H6, and C6H6) in the Kohn-Sham limit. Individual results of calculations using dedicated families of Jensen's basis sets (pcS-n and pcJ-n) were fitted toward the complete basis set limit (CBS) using a simple two-parameter formula. Several density functionals were used; calculated vibrational corrections (ZPV) applied; and, for comparison purposes, similar calculations performed using RHF, MP2, SOPPA, SOPPA(CCSD), and CCSD(T) methods and additionally, the aug-cc-pVTZ-J basis set. Finally, the CBS estimated results were critically compared with earlier reported literature data and experimental results. Among 42 studied DFT methods, the KTn and "pure" functionals produced the most accurate heavy atom isotropic nuclear shieldings.
authors.affiliation: University of Opole, Faculty of Chemistry, Poland, Department of Molecular Spectroscopy, Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic, and University of Silesia, Institute of Chemistry, Katowice, Poland.
authors.forename: Teobald
authors.initials: T
authors.lastname: Kupka
authors.affiliation: University of Opole, Faculty of Chemistry, Poland, Department of Molecular Spectroscopy, Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic, and University of Silesia, Institute of Chemistry, Katowice, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Stachów
authors.affiliation: University of Opole, Faculty of Chemistry, Poland, Department of Molecular Spectroscopy, Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic, and University of Silesia, Institute of Chemistry, Katowice, Poland.
authors.forename: Marzena
authors.initials: M
authors.lastname: Nieradka
authors.affiliation: University of Opole, Faculty of Chemistry, Poland, Department of Molecular Spectroscopy, Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic, and University of Silesia, Institute of Chemistry, Katowice, Poland.
authors.forename: Jakub
authors.initials: J
authors.lastname: Kaminsky
authors.affiliation: University of Opole, Faculty of Chemistry, Poland, Department of Molecular Spectroscopy, Institute of Organic Chemistry and Biochemistry, Prague, Czech Republic, and University of Silesia, Institute of Chemistry, Katowice, Poland.
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Pluta