Electric field gradient calculations in paramagnetic compounds using the PAW approach. Application to 23 Na NMR in layered vanadium phosphates

This article presents ab initio calculations of electric field gradient (EFG) parameters as a tool for the structural characterization of paramagnetic crystalline compounds. Previously reported 23 Na NMR parameters of vanadium + IV containing vanado‐phosphate compounds were computed within density functional theory using both cluster and fully periodic approaches. Quadrupolar parameter values measured by 23 Na NMR experiments were reproduced with a level of accuracy comparable to that achievable in diamagnetic compounds and allowed the assignment of observed 23 Na NMR signals. This work demonstrates the utility of the periodic planewave pseudopotential + PAW approach for the calculation of EFG parameters in paramagnetic compounds. Copyright © 2010 John Wiley & Sons, Ltd.