On the nature and role of Fe³⁺ ions in oxide and fluoride glasses

Abstract

Fe3+ doped oxide and fluoride glasses were investigated by ESR spectroscopy at 4.2 K. For the first time, the resulting complex spectra could be completely reproduced starting from a diagonalization of the S = 5/2 spin‐hamiltonian, including the appropriate zero‐field splitting components D and E, and using distributions for the fourth order spin coupling parameters. By careful analysis of the differentiated and integrated experimental and calculated spectra it could be shown, that if only Fe3+ point defects are present in glasses, the main ESR intensity covers the range of g'∼4.3. Since all experimental spectra yield remarkable contributions in the range of g'∼2 there is evidence for the existence of magnetically interacting clusters in the glasses. Differences between Fe3+ doped oxide and fluoride glasses essentially concern the concentration dependent spectral pattern and the low‐temperature spin relaxation behaviour.

Raman and EPR studies of β-irradiated oxide glasses: The effect of iron concentration

“…The pristine ones display no EPR resonance except the EPR line at g $ 4.3 corresponding to the Fe 3+ ion [16]. Fig.…”