Figure 2. The OTP non-ergodicity factor f_c (inset) and the stretched exponent β_S obtained from the correlators and compared with the previous one obtained in the MCT frame.

The Debye-Waller factor f_c is reported for different temperatures in the range 243 < T < 263 K. The dashed line represents the MCT scaling law prediction, as the temperature decreases below T_B: f_c ~ |T_B − T|^1/2. Together with actual data for β_S (dark red circles) the figure reports the values of the stretched exponent measured in previous experiments: PCS (open green diamonds³⁶) and TFPI/DM (blue circles³⁵).