Errico, L. A.Fabricius, G.Rentería, MPresa Muñoz del Toro, Patricia de laForker, M.2023-06-202023-06-202002-07-290031-900710.1103/PhysRevLett.89.055503https://hdl.handle.net/20.500.14352/60212©2002 The American Physical Society. This work was supported by CONICET, ANPCyT, F. Antorchas (Argentina), and DFG (Germany). M. R. is indebted to J.-P. Dallas (CECM, Vitry) for the single crystals orientation and to A. Traverse (LURE) for valuable support on this project. We thank R. Vianden (ISKP) and A. F. Pasquevich (UNLP) for critical comments.We present an ab initio study of the relaxations introduced in TiO₂ when a Cd impurity substitutes a Ti atom and an experimental test of this calculation by a perturbed-angular-correlation (PAC) measurement of the orientation of the electric-field gradient (EFG) tensor at the Cd site. The ab initio calculation predicts strong anisotropic relaxations of the nearest oxygen neighbors of the impurity and a change of the orientation of the largest EFG tensor component, V_(33) , from the [001] to the [110] direction upon substitution of a Ti atom by a Cd impurity. The last prediction is confirmed by the PAC experiment that shows that V_(33) at the Cd site is parallel to either the [110] or the [1͞10] crystal axis.engjournal articlehttp://dx.doi.org/10.1103/PhysRevLett.89.055503https://journals.aps.orgopen access538.9Electric-field gradientsAb-initioTemperature-dependenceApproximationCd-111OxidesSitesFísica de materialesFísica del estado sólido2211 Física del Estado Sólido