The application of a modified Simon-Glatzel-type relation [Z.Anorg.Allg.Chem.178,309 (1929)] for the pressure evolution of the glass temperature is presented,namely,T_g(P) = T_g~0[1+DELTA P/ (pi+P_g~0)]~(1/b) exp[-(DELTA P/c)],where (T_g~0,P_g~0) are the reference temperature and pressure,DELTA P = P-P_g~0,-pi is the negative pressure asymptote,b is the power exponent,and c is the damping pressure coefficient.The discussion is based on the experimental T_g(P) data for magmatic silicate melt albite,polymeric liquid crystal P8,and glycerol.The latter data are taken from Cook et al.[J.Chem.Phys.100,5178 (1994)] and from the authors' dielectric relaxation time (tau(P)) measurements,which employs the novel pressure counterpart of the Vogel-Fulcher-Tammann equation: tau(P) = tau_0~P exp[D_P DELTA P/(P0-P)],where DELTA P=P-P_(SL) (P_(SL) is the stability limit hidden under negative pressure),P0 is the estimation of the ideal glass pressure,and D_P is the isothermal fragility strength coefficient.Results obtained suggest the hypothetical maximum of the T_g(P) curve,which can be estimated due to the application of the supporting derivative-based analysis.A hypothetical common description of glass formers characterized by dT_g/dP>0 and dT_g/dP<0 coefficients is suggested.Finally,the hypothetical link between molecular and colloidal glass formers is recalled.
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