Praseodymium in heavy metal oxyfluoride glass systems

A new thermally stable glasses based on P2O5-InF3 and PbF2-B2O3 containing Pr3+ ions were prepared, which belong to wide family of heavy metal oxyfluoride systems. Influence of P2O5 content on thermal, structural and optical behavior of multicomponent InF3-based glass has been investigated, whereas the second oxyfluoride system in the case of total substitution PbO by PbF2 has been analyzed. A large value of stability parameter Delta T close to 157 degrees C was obtained for Pr doped oxyfluoride glass with 8% of P2O5 content. With further increasing P2O5 content stability parameter Delta T decreased and several crystalline peaks related to InOF phase appeared, what was stated by X-ray diffraction. Shift of luminescence lines has been observed for both heavy metal oxyfluoride glass systems. However, shift direction depends on kind of additives (oxide or fluoride components) to the basic matrix. Incorporation of P2O5 results in shift of red luminescence due to the D-1(2)-H-3(4) transition of Pr3+ ions in direction to longer wavelengths. The opposite situation is observed for glass based on PbF2-B2O3 emitting reddish-orange light. Substitution PbO by PbF2 leads to shift of luminescence band in direction to shorter wavelengths.