EPR and Magnetic Susceptibility Investigations of Fe Containing TeO2-B2O3-SrF2 Glasses
EPR and Magnetic Susceptibility Investigations of Fe Containing TeO_2-B_2O_3-SrF_2 Glasses

Iron ions were used as probes to explore the structural and magnetic properties of 70TeO(2). 25B(2)O(3). 5SrF(2) vitreous matrix. The distribution of Fe3+ ions on different structural aggregates was revealed by means of EPR, as depending on Fe2O3 concentration. Strongly distorted octahedral sites were detected for the isolated paramagnetic ions, and also clusters of Fe ions especially at high Fe2O3 content of samples. Magnetic susceptibility measurements evidenced both dipole-dipole and superexchange type interactions involving iron ions. Mixed valence states of iron ions were also detected.