Ab initio and Mössbauer study of the electronic structure and hyperfine parameters of ZnFe2O4 with defects

J. J. MELO QUINTERO; K. L. SALCEDO RODRÍGUEZ; G. A. PASQUEVICH; P. MENDOZA ZÉLIS; S. J STEWART; C. E. RODRÍGUEZ TORRES; L. A. ERRICO

Hamburgo

Conferencia; International Conference on the Applications of the Mössbauer Effect; 2015

We present a combined Mössbauer and ab initio study on the influence of oxygen-vacancies on the hyperfine and magnetic properties of the ZnFe2O4 spinel ferrite [1-3]. Samples with different degree of oxygen-vacancies were obtained from zinc ferrite powder that was thermally treated at different temperatures up to 650 ºC under vacuum. Theoretical calculations of the hyperfine parameters, magnetic moments and magnetic alignment have been carried out considering different defects such as oxygen-vacancies and cation inversion. We show how theoretical and experimental approaches are complementary to characterize the local structure around Fe atoms and interpret the observed changes in the hyperfine parameters as the level of defects increases