Raman spectroscopic study of layered quaternary ferrite Ba12Fe28Ti15O84

Ba-Fe-Ti oxides are nowadays attracting considerable interest for the production of permanent magnets and microwave devices, due to their high dielectric constant. Among these materials, recently the quaternary ferrite Ba12Fe28Ti15O84 (BFT) was discovered to possess ferrimagnetic properties at room temperature with a main magnetic transition at about 420K and complete disappearance of magnetisation above 700K. In this study, we report for the first time on the Raman spectrum of BFT samples prepared with different methods. Raman spectra were recorded in dependence of temperature and a preliminary assignment of modes was attempted. Coupling the Raman results with previous magnetic studies allowed gaining more insight on the structural mechanism at play in correspondence of the main magnetic transition.