Experimental nonevidence of fragile-to-strong crossover

This study explores the viscosity behavior of the Ge-Se chalcogenide glass-forming system. Four compositions containing 5, 10, 15, and 20 at. % germanium were examined. Viscosity measurements were performed over a broad range, spanning approximately 13 orders of magnitude, by combining the pressure-assisted melt filling technique with penetration and parallel-plate viscometry. The results demonstrate that no fragile-to-strong crossover occurs in any of the studied compositions.