Anisotropic relaxations introduced by Cd impurities in Rutile TiO2: first-principles calculations and experimental support

L. A. ERRICO; G. FABRICIUS; M. RENTERÍA; P. DE LA PRESA; M. FORKER

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Lugar: New York; Año: 2002 vol. 89 p. 55503 - 55507

0031-9007

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, V33, 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 V33 at the Cd site is parallel to either the 110 or the 110 crystal axis.