Zn-67 NMR has been used as a probe to measure the electric field gradients at the metal site in the zinc halides ZnF2, gamma-ZnCl2, ZnBr2 and ZnI2 and RbZnCl4 at room temperature. In addition two hydration states have been detected for ZnSO4. For ZnF2 and gamma-ZnCl2 an ab initio calculation of the electric field gradient at the Zn site using the WIEN 97 code agrees well with the experimentally observed values. (C) 2003 Elsevier B.V. All rights reserved.