A Systematic Comparison of Second-Order Polarization Propagator Approximation and Equation-of-Motion Coupled Cluster Singles and Doubles C−C, C−N, N−N, C−H, and N−H Spin−Spin Coupling Constants

Abstract

Ab initio one-, two-, and three-bond C-C, C-N, and N-N spin-spin coupling constants, and one-bond C-H and N-H coupling constants have been computed using two different theoretical methods, SOPPA/ (qzp,qz2p) and EOM-CCSD/(qzp,qz2p). Both EOM-CCSD (equation-of-motion coupled cluster singles and doubles) and SOPPA (second-order polarization propagator approximation) coupling constants correlate linearly with experimental data. In the great majority of cases, the computed EOM-CCSD C-C, C-N, N-N, and N-H coupling constants are in better agreement with experimental data than SOPPA values, although both levels of theory provide reasonable estimates of these couplings. EOM-CCSD consistently underestimates one-bond C-H coupling constants by about 10 Hz, and SOPPA values of 1 J(C-H) are in better agreement with experimental data. The performance of SOPPA supports its use in future studies of coupling constants involving C, N, and H in larger chemical and biological systems. † Part of the "Rusell M. Pitzer Festschrift".

Theoretical prediction of nuclear magnetic shieldings and indirect spin-spin coupling constants in 1,1-, cis-, and trans-1,2-difluoroethylenes

“…In Table VIII are gathered all Ramsay terms of spin-spin couplings, the total theoretical value predicted at BHandH/aug-pcJ-2 level of theory and the available calculated 70,71,75,77,79,113 and experimental 22-25, 107, 114-117 value for the studied molecules. In case of ethylene 79,86,114 this level of theory predicts fairly accurate coupling constants (RMS deviation of 3.3 Hz, no correction for ZPV included).…”

Do corresponding coupling constants in hydrogen-bonded homo- and hetero-chiral dimers differ?

“…The EOM-CCSD method with the Ahlrichs (qzp,qz2p) basis set has been shown to yield coupling constants in good agreement with experimental values for molecules. [19][20][21][22] Its application to hydrogen-bonded complexes has provided insight into experimentally determined coupling constants, 23 and the predicted relationship between 2h J(N-N) and the N-N distance for N-HÁÁÁN hydrogen bonds 24 has been verified experimentally. 25 Finally, the computed signs and magnitudes of 2h J(X-Y), 1h J(H-Y), and 1 J(X-H) for X-HÁÁÁY hydrogen bonds have been used successfully to characterize hydrogen-bond type.…”

Benchmark calculations of 29Si–1H spin–spin coupling constants across double bond

“…Recently, a general Second‐Order Polarization Propagator Approach, SOPPA, has been extensively used for the high‐level calculations of different types of spin–spin coupling constants in the medium‐sized organic molecules. Among others, a good performance of the SOPPA method has been demonstrated for the 1 H– 1 H, 13 C– 1 H and 13 C– 13 C couplings in a large number of saturated carbocycles, nitrogen‐containing heterocycles, and functional derivatives of aldehydes and ketones, the 15 N– 1 H, 15 N– 13 C and 15 N– 15 N couplings in the cyclic and open‐chain nitrogen‐containing compounds, the 19 F– 1 H, 19 F– 13 C and 19 F– 19 F couplings in fluorobenzenes, the X … H … Y (X, Y = 17 O, 15 N, 19 F) couplings across hydrogen bonds, the 31 P– 1 H couplings in organic phosphines and phosphine chalcogenides, the 77 Se– 1 H couplings in selanylalkenes, five‐ and six‐membered selenium‐containing heterocycles, and even in much larger systems like selenosugars . Also, SOPPA(CCSD) approach was successfully employed for smaller systems, presenting a difficult case for methods based on perturbation theory .…”