Measured and ideal glass transition temperatures of glass-forming liquids

Herein, measured and ideal glass transition temperatures of glass-forming liquids have been investigated. The value of T0/Tg increases with increasing fragility parameter m or decreasing strength parameter D (where Tg and T0 are the measured and ideal glass transition temperatures, respectively). We utilize T0/Tg values to classify various glass-forming liquids into three broad categories, which are strong, metallic glass-forming (intermediate) and fragile liquids. The result reveals that strong liquids with 15.25 < m ≤ 30 (or 37.3 ≤ D) have 0 < T0/Tg ≤ 0.49. By contrast, fragile liquids obtain 0.82 ≤ T0/Tg ≤ 0.94 when m values lie in 100 ≤ m ≤ 214 (or 1.8 ≤ D ≤ 9.1). Metallic glass-forming liquids have 0.52 ≤ T0/Tg ≤ 0.77 when m values have 32 ≤ m ≤ 66 (or 10.8 ≤ D ≤ 32.8).