Magnetic Properties of Rapidly Quenched Ternary Oxides Li2O–Bi2O3–Fe2O3System

Abstract
Ternary oxides in the system Li2O–Bi2O3–Fe2O3were prepared by rapid quenching from the melt by means of a twin-roller apparatus. As-quenched samples turned out to be X-ray amorphous, and ferromagnetic behaviour was observed at room temperature. Particularly, the amorphous (Li2O)25(Bi2O3)25(Fe2O3)50specimen has magnetization value of about 4.5 emu/g (15 kOe) at room temperature. This specimen shows an irreversible thermomagnetization process below about 200 K in a weak magnetic field, indicating the existence of magnetic frustration. The57Fe Mössbauer absorption spectra indicate that this specimen is composed of two different phases, short-range antiferromagnetic and ferromagnetic, and that the latter is less disordered (or crystallinelike). The magnetic frustration seems to be caused by the competition between exchange interactions at the interface of these phases.