Pressure dependence of the glass temperature in supercooled liquids

The description of the pressure evolution of the glass temperature T-g(P) based on experimental data for diethyl phtalate is discussed. First, parameterizations of T-g(P) experimental data applied are briefly given. Then a novel relation based on the modified Simon-Glatzel equation is proposed. Its applications may result in the appearance of the asymptotic temperature (theta) and the asymptotic pressure (pi) previously postulated [E. Donth, The Glass Transition: Relaxation Dynamics in Liquids and Disordered Materials, Springer Series in Material Sci. II (Springer, Berlin, 1998), Vol. 48, pp. 6, 375]. The asymptotic pressure is hidden in the negative pressure domain. Such asymptotic behavior was absent for parameterizations of T-g(P) data in glassy liquids applied up to now.