⁶⁷Zn NMR chemical shifts and electric field gradients in zinc complexes: A quantum chemical investigation

We have used quantum chemical methods to predict ⁶⁷Zn NMR chemical shifts as well as quadrupole coupling constants (C_Q) in a series of biomimetic and inorganic zinc complexes. The ⁶⁷Zn chemical shifts are predicted with an R² = 0.975, corresponding to a 24.3 ppm or 6.7% error over the entire 365 ppm ⁶⁷Zn chemical shift range. The ⁶⁷Zn C_Q values are predicted with an R² = 0.991, corresponding to a 1.17 MHz or 3.0% error over the entire 38.75 MHz range. The ₆₇Zn NMR shifts in a series of complexes containing N,O ligands are, in general, highly correlated with the number of oxygen ligands. The ability to compute ₆₇Zn NMR shifts as well as C_Q values opens up the possibility of using both of these properties in structure determination or refinement in proteins.