Stephan P. A. Sauer

University of Copenhagen, Department of Chemistry, Faculty Member

Followers

116

Following

Co-authors

Public Views

Address: Department of Chemistry
University of Copenhagen
DK-2100 Copenhagen Ø
Denmark, Europe

less

InterestsView All (9)

Uploads

Papers by Stephan P. A. Sauer

On the Unexpected Accuracy of the M06L Functional in the Calculation of 1JFC Spin–Spin Coupling Constants

Journal of Chemical Theory and Computation, Nov 9, 2021

One-bond spin-spin coupling constants (SSCCs) between F and C are computed with density functiona... more One-bond spin-spin coupling constants (SSCCs) between F and C are computed with density functional theory (DFT). Surprisingly, M06L stands out for its striking accuracy, outperforming any other investigated functional, including PBE0, otherwise considered one of the most reliable for couplings involving F. Although the computation of nuclear magnetic resonance (NMR) parameters involving F is known to be a challenging task, even with a rather small basis set as pcJ-1, M06L provides results with a MAD = 11.7 Hz, whereas the average deviation gets as much as 5 times larger for PBE0 (MAD = 60.0 Hz). In the context of SSCCs on the order of 300 Hz, this is particularly remarkable. We find that the accuracy of M06L/pcJ-1 in predicting 1JFC constants does not stem from a well-suited exchange or correlation part of the functional. Instead, it is believed to arise from a fortuitous cancellation of errors, as revealed by investigating the convergence of the basis set. Our findings also indicate that 1JFC constants are highly dependent on the amount of exact exchange included in the expression of the functional, with large fractions being critically important to achieving satisfactory results. Studying the effects of the geometry on 1JFC, we find that optimizing the geometry at the level of theory used to calculate SSCCs generally improves the quality of the results, although the combination of a M06-2X/aug-cc-pVTZ geometry with M06L/pcJ-1 1JFC constants best reproduces the experimental data for organofluorine compounds (with the exception of fluoroalkenes).

Approximations to Exact Perturbation and Response Theory Expressions

Oxford University Press eBooks, Aug 25, 2011

Examples of Calculations and Practical Issues

Oxford University Press eBooks, Aug 25, 2011

Importance of Relativistic Effects for Carbon as an NMR Reporter Nucleus in Carbide-Bridged [RuCPt] Complexes

Organometallics, May 10, 2021

Carbide-bridged ruthenium platinum complexes of the general formula trans-(Cy3P)2Cl2Ru≡C–PtCl2-L ... more

A relation between the rotational g-factor and the electric dipole moment of a diatomic molecule

Chemical Physics Letters, Dec 1, 1998

ABSTRACT

The computation of Karplus equation coefficients and their components using self-consistent field and second-order polarization propagator methods

Molecular Physics, Dec 10, 2000

... (4) * Author for correspondence. e-mail: m.grayson@shef. + c4 cos(4e) ac.uk Molecular Physics... more

Theoretical estimates of the rotational g-factor, magnetizability and electric dipole moment of GaH

Chemical Physics Letters, Sep 1, 1996

ABSTRACT

Experimental and Theoretical Estimates of the Rotational g Factor of AlH in the Electronic Ground State X1.SIGMA.+

The Journal of Physical Chemistry, Sep 1, 1994

... comparison between data in Table I1 and the radial function ZtlHd according to the coefficien... more

Benchmarking Correlated Methods for Static and Dynamic Polarizabilities: The T145 Data Set Evaluated with RPA, RPA(D), HRPA, HRPA(D), SOPPA, SOPPA(CC2), SOPPA(CCSD), CC2, and CCSD

Journal of Physical Chemistry A, Apr 26, 2021

Due to the importance of predicting static and dynamic polarizabilities, the performance of vario... more Due to the importance of predicting static and dynamic polarizabilities, the performance of various correlated linear response methods including random phase approximation (RPA), RPA(D), higher-order random phase approximation (HRPA), HRPA(D), second-order polarization propagator approximation (SOPPA), SOPPA(CC2), SOPPA(CCSD), CC2, and CCSD has been evaluated against CCSD(T) (static case) and CCSD (dynamic cases) for the T145 set of 145 organic molecules. The benchmark reveals that the HRPA(D) method has the best performance for both static and dynamic polarizabilities apart from CCSD. RPA(D) ranks second for the dynamic cases and third for the static case. Using coupled-cluster amplitudes in SOPPA(CCSD) and SOPPA(CC2), the SOPPA results are significantly improved. The HRPA method has the largest deviations from the reference values for both cases. In general, according to the performance and computational cost of the methods, the HRPA(D) and RPA(D) methods are proposed for calculations of static and dynamic polarizabilities of this and similar sets of molecules.