Bond Strength-Coordination Number Fluctuations and the Fragility of Some Ion Conducting Oxide and Chalcogenide Glass Forming Liquids
نویسندگان
چکیده
The concept of fragility has been used widely to characterize the temperature dependence of the viscosity of glass forming liquids. According to a model proposed by one of the authors, the fragility is determined by the relaxation of structural units that form the melt, and is described in terms of the bond strength, coordination number and their fluctuations. In the present contribution, the model is applied to investigate the temperature dependence of the viscosity of some ion conducting oxide and chalcogenide glass forming liquids. From the analysis of the model, physical quantities, such as the number of bonds that must be broken to observe the viscous flow is obtained. The analysis suggests also that good ionic conductors have an intermediate value of fragility.
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