Mössbauer and FP-LAPW study of Fe-doped TiO2 and SnO2

A.F. CABRERA; L. ERRICO; A. MUDARRA NAVARRO; C.E. RODRÍGUEZ TORRES; M. RENTERÍA; F.H. SÁNCHEZ; M. WEISSMANN

CAC (CNEA), Buenos Aires

Congreso; "At the Frontiers of Condensed Matter Physics III"; 2006

CAC (CNEA) y Depto. de Física (UBA), Argentina

During the last years the study of transition metal-doped TiO2 and SnO2semiconductors has become a topic of interest, not only because of the many currentindustrial applications of these materials, as for example in catalysis, but also because oftheir potential use in spintronic devices.There is a great deal of new experimental and theoretical work on these TM-dopedsystems (TM= Mn, Co, Fe, Ni, Cu), focused on their magnetic properties. In the case of Fedoping, Mössbauer studies were performed in order to elucidate the local atomic structuresassociated to the observed interactions. Despite the several reports published on quadrupolesplitting data, a unique consensus on the hyperfine parameters associated to Fesubstitutional in the rutile structure has not been achieved yet. Several questions remainopen concerning the Fe dopants location in the host structure, and/or the short range ordersaround impurities, as well as the assignment of the observed hyperfine interactions.In 2002 we demonstrated the capability of the ab initio full potential linearizedaugmented plane waves (FP-LAPW) method to predict the hyperfine parameters atimpurity sites. Following this approach, in this work we present a comparative Mössbauerand FP-LAPW study of the hyperfine parameters at Fe impurity in the rutile phase of TiO 2and SnO2.