An assessment of the concept of fragility

Abstract

The concept of "fragility", which was introduced to characterize the degree of super-Arrhenius temperature dependence of the relaxation time and transport coefficients, has since been taken as a key quantity that seems to correlate with other properties of glass-forming liquids and polymers. With the goal of assessing the usefulness and the robustness of the concept, we address here several questions: How to best quantify fragility? How significant are the observed differences in fragility? Is fragility connected to "cooperativity" and collective behavior?

arXiv comment4 pages. Proceedings of the Symposium on "Fragility of Glass-forming Liquids", A. L. Greer, K. F. Kelton, and S. Sastry eds., TRIPS 13 (New Dehli, 2014)