63Cu and 197Au nuclear quadrupole moments from four-component relativistic density-functional calculations using correct long-range exchange

The electric field gradient in late transition metal compounds is incorrectly determined by most density functionals. We show that the coupling of short-range density functional based with long-range wave function based methods using a reparametrization of the Coulomb-attenuated Becke three-parameter Lee-Yang-Parr approximation gives reliable results for the electric field gradients of copper and gold for a series of compounds. This results in nuclear quadrupole moments of -0.208 b for Cu-63 and +0.526 b for Au-197 in good agreement with experimental values of -0.220(15) and +0.547(16)b, respectively.