Acoustic properties, elasticity, and equation of state of glycerol under pressure

Abstract

We employed high-pressure Brillouin scattering to study the pressure dependencies of acoustic modes of glycerol up to 14 GPa at 300 K. We observed longitudinal acoustic velocities and transverse acoustic velocities for the first time from 5 to 14 GPa. The results allow the determination of a complete set of elastic properties and an accurate determination of the pressure–volume (P–V) equation of state (EOS). EOS parameters, K0 = 14.9 ± 1.8 GPa and K′0 = 5.6 ± 0.5, were determined from fits to the data from ambient pressure to 14 GPa. Direct volume measurements of the P–V EOS are consistent with those determined by Brillouin scattering. A deviation from a Cauchy-like relationship for elastic properties was observed, and the pressure dependencies of the photoelastic constants and relaxation times were documented from 5 to 14 GPa. These results have broad implications for glass-forming liquids, viscoelastic theory, and mode coupling theory.

Poisson’s Ratio of Glasses, Ceramics, and Crystals

“…However, the pressure-dependence of Poisson's ratio is very small, and their values of Poisson's ratio are about 0.35-0.37 between 1 and 12 GPa. The pressure-dependence of Poisson's ratio of glycerol is also shown in Figure 9b [39]. Glycerol undergoes a liquid-glass transition at about 5 GPa, and above this pressure, the TA mode was observed in a glassy state using Brillouin scattering.…”

“…Figure 9. Pressure-dependence of (a) Poisson's ratio ν and the bulk modulus B of Baltic amber measured based on Brillouin scattering[26], and (b) pressure-dependence of Poisson's ratio of glycerol[39].…”