Scalar relativistic correction to nucleus-independent chemical shifts of coinage-metal compounds: How does the pseudopotential approximation perform?

The performance of commonly used pseudopotentials for calcns. of nucleus-independent chem. shifts (NICS) at the center of coinage-metal rings (M4Li2 (D4h), M = Cu, Ag, Au) was studied. The scalar relativity, which has a nonnegligible effect on NICS, is accurately described by the pseudopotential approxn. Overall, good agreement was obtained with all-electron relativistic methods, however, careful comparisons with these calcns. and consideration for large triple-zeta basis sets are recommended when aiming to accurately define the relative degree of diatropicity among compds. [on SciFinder (R)]