Temperature dependence of the EFG at Cd-doped Lu2O3: How ab initio calculations can complement PAC experiments

We report an ab initio study of the temperature dependence of the electric‐field gradient (EFG) tensor at Cd impurities replacing cations in Lu2O3. Calculations were performed with the Full‐Potential Linearized‐Augmented Plane Wave method that allows us to treat the electronic structure and the processes induced by the impurity in the host‐lattice without the use of external parameters. In this new insight, the EFG thermal dependence arises from the ionization of an impurity acceptor level introduced in the band‐gap of Lu2O3 by Cd impurities, in good agreement with a previously proposed two state model. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)