Institute for Multidisciplinary Research, University of Belgrade
Abstract
Bismuth ferrite (BiFeO3) is one of the most studied multiferroic system. BiFeO3
has been synthesized by controlled hydrothermal process, where the particles of
small sizes and with high purity were obtained. Structural analysis showed that nonannealed powder can be perfectly fitted to rhombohedral space group R3c as αBiFeO3 phase. In addition, a structure prediction has been performed and 11
additional BiFeO3 modifications have been proposed. In the next phase, an ab initio
optimization of predicted structures has been performed and the structure of the γphase has been elucidated.
In addition, electronic and magnetic properties of BiFeO3 were investigated
using combination of experimental and theoretical methods. Theoretical studies
were performed using a full potential linearized augmented plane-waves plus local
orbital (FP(L)APW+lo) method, based on density functional theory (DFT). HRTEM
analysis confirmed existence of twin stacking faults, which are responsible for
enhanced magnetic properties. EPR measurements suggested existence of electrons
trapped by vacancies or defects, while magnetic behavior of synthesized material
was investigated by SQUID