Temperature dependence of density, thermal expansion coefficient and shear viscosity of supercooled glycerol as a reflection of its structure

The relationship of the microstructure of supercooled, highly viscous glycerol to the temperature dependence of its density, thermal expansion coefficient, and shear viscosity are discussed. The character of this temperature dependence at the transition from low viscosity state to the solid amorphous state solidified state without nuclei is described with help of function psi, which can be interpreted as the effective number of degrees of freedom responsible for the change of viscosity of glycerol over a broad range; these degrees of freedom are those related to the alpha-relaxation process. It is shown that the change in effective activation energy of the viscosity is completely determined by the parameter psi. The change in the shear viscosity of glycerol due to the influence of the solid-phase nuclei is considered. It is shown that the introduction of the parameter phi, equal to the specific volume occupied by the nuclei of the solid phase, together with psi provides a natural explanation of the temperature dependence of density and thermal expansion coefficients of glycerol in its liquid, solid amorphous, glassy, and crystal states. The peculiarities of the temperature dependence of phi(T) and psi(T) for glycerol and o-terphenyl are compared

Dielectric permittivity of glycerol in the high viscosity region

The temperature dependence of the quasistatic dielectric permittivity of highly viscous glycerol is considered in terms of the approach developed in the work [I.V. Blazhnov, N.P. Malomuzh, S.V. Lishchuk, J. Chem. Phys. 121 (2004) 6435]. The microinhomogeneous structure of supercooled glycerol and the frequency dispersion of dielectric permittivity play substantial role in its description. The temperature dependence of the static dielectric permittivity of liquid that surrounds nuclei is determined. The temperature dependencies of the effective polarizability and the mean square value of the dipole moment of molecules in liquid that surrounds nuclei are discussed