Study of niobium (Nb5+) substituted four-layer Aurivillius compound Bi5FeTi3O15.

In the present work, we report the study of Nb5+ substitution at the B-site of the four layer Aurivillius compound Bi5FeTi3O15 (BFTO). Structural and micro-structural properties are studied with x-ray diffraction, scanning electron microscopy and Raman spectroscopy measurements. The temperature dependent magnetization study shows weak anti-ferromagnetic behavior with the substitution of Nb5+ in the BFTO compound, which otherwise doesn't show any long-range magnetic ordering. The room temperature Mössbauer spectroscopy measurement confirms the Fe3+ state and also rules out the presence of any iron oxide impurity phases in the studied compounds. [ABSTRACT FROM AUTHOR]