1992/01/01 by Schels, Thomas, B. Camara, Camara, Boubacar +2
Materials Science · Engineering · #Glass properties and applications #Nuclear materials and radiation effects #Recycling and utilization of industrial and municipal waste in materials production
paper · doi:10.34657/14040
Lithium, sodium and potassium silicate glasses containing different Fe<sub>2</sub>O<sub>3</sub> amounts were irradiated with γ- and X-rays and investigated by using ESR. The well-known iron resonances at g = 4.2 and g = 1.99 show a characteristic behaviour at the transition from lithium to potassium and by changing the Fe<sub>2</sub>O<sub>3</sub> concentration. The resonance at g = 4.2 decreases from lithium to potassium, whereas the resonance at g = 1.99 increases. The concordance of the intensity course of the two resonances with the preference of the alkali metals to take tetrahedral or octahedral coordination is an interesting support for the attribution of g = 4.2 to 4-fold coordinated Fe<sup>3+</sup> and g = 1.99 to 6-fold coordination of this ion. γ- and X-rays induce the same defect centres (colour centres). These centres are characterized by a strong resonance at g = 2.01. All radiation defects have a strong dependence on the type of alkali metal - they increase from lithium to potassium - and on the Fe<sub>2</sub>O<sub>3</sub> concentration of the glasses. In glasses which contain a very small quantity of Fe<sub>2</sub>O<sub>3</sub> the irradiation induces more defects than in the corresponding iron-free glasses. With increasing Fe<sub>2</sub>O<sub>3</sub> content the glasses become more resistant against irradiation and at a high concentration no more defects can be produced.