Vibrational Corrections to NMR Spin-Spin Coupling Constants from Relativistic Four-Component DFT Calculations.

Zero-point vibrational (ZPV) corrections to the nuclear spin-spin coupling constants have been calculated using four-component Dirac-Kohn-Sham DFT for HX (where X = O, S, Se, Te, Po), XH (where X = N, P, As, Sb, Bi), and XH (where X = C, Si, Ge, Sn, and Pb) molecules and for HC≡CPbH. The main goal was to study the influence of relativistic effects on the ZPV corrections and thus results calculated at relativistic and nonrelativistic approaches have been compared. The effects of relativity become notable for the ZPV corrections to the spin-spin coupling constants for compounds with lighter elements (selenium and germanium) than for the spin-spin coupling constants themselves. In the case of molecules containing heavier atoms, for instance BiH and PbH, relativistic effects play a crucial role on the results and approximating ZPV corrections by the nonrelativistic results may lead to larger errors than omitting ZPV corrections altogether.