Raw MDSC data obtained at a heating rate of 1 °C/min with an angular frequency of 0.00833 Hz (120 s period) and an amplitude of 0.8 °C. Black lines display the actual input (modulated heating rate) and output (modulated heat flow) signals and red lines show the temporal averages.
Real part Cp′ and imaginary part Cp ″ of the complex heat capacity for an unannealed selenium glass obtained from the signals shown in Fig. 1 .
Average heat capacity of a Se sample after long anneals. The overshoot in average heat capacity corresponds to the enthalpy regained during the reheating and increases as a function of annealing time.
Lissajous curves of a Se sample annealed at 22 °C for 192 h and reheated at a heating rate of 2 °C/min, an amplitude A T = 1 °C, and a period of 180 s through the glass transition.
Lissajous curves of a Se sample annealed at 25 °C for 249 h and reheated at a heating rate of 1 °C/min, an amplitude A T = 0.8 °C, and a period of 120 s (a) in the glassy and liquid domain and (b) through the glass transition.
Correction operated on the phase angle data for obtaining the FWHM of Cp ″.
Monotonic shift of T ω after long annealing periods indicates the monotonic decrease in average fictive temperature.
(a) The difference in integrated area between the reference and annealed heat capacity curves characterizes the average enthalpy release during the relaxation. Released enthalpy follows a stretched exponential decay profile. (b) Computed evolution of average enthalpy loss for a simulation performed following exactly the same heat treatment conditions.
(a) Nonmonotonic evolution of enthalpy fluctuations expressed as FWHM values of Cp ″ peak during extended annealing at 298 K. (b) Computed evolution of enthalpy fluctuations modeled following the same heat treatment.
(a) Change in the Cp ″ peak shape and (b) computed distribution of enthalpy fluctuations during annealing at 298 K.
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