Thermodynamic Scaling of the Viscosity of Van Der Waals, H-Bonded, and Ionic Liquids
arXiv:cond-mat/0607611 · doi:10.1063/1.2346679
Abstract
Viscosities and their temperature, T, and volume, V, dependences are reported for 7 molecular liquids and polymers. In combination with literature viscosity data for 5 other liquids, we show that the superpositioning of relaxation times for various glass-forming materials when expressed as a function of TV^g, where the exponent g is a material constant, can be extended to the viscosity. The latter is usually measured to higher temperatures than the corresponding relaxation times, demonstrating the validity of the thermodynamic scaling throughout the supercooled and higher T regimes. The value of g for a given liquid principally reflects the magnitude of the intermolecular forces (e.g., steepness of the repulsive potential); thus, we find decreasing g in going from van der Waals fluids to ionic liquids. For strongly H-bonded materials, such as low molecular weight polypropylene glycol and water, the superpositioning fails, due to the non-trivial change of chemical structure (degree of H-bonding) with thermodynamic conditions.
16 pages 7 figures
References in corpus (1)
Cited by in corpus (18)
- Thermodynamic scaling of diffusion in supercooled Lennard-Jones liquids
- An equation for the description of volume and temperature dependences of the dynamics of supercooled liquids and polymer melts
- Pressure-energy correlations and thermodynamic scaling in viscous Lennard-Jones liquids
- Density scaling in viscous liquids: From relaxation times to four-point susceptibilities
- Determination of the Thermodynamic Scaling Exponent from Static, Ambient-Pressure Quantities
- New correlations between viscosity and surface tension for saturated normal fluids
- Thermodynamic scaling of vibrational dynamics and relaxation
- Corroborative evidences of TVgamma-scaling of the alpha-relaxation originating from the primitive relaxation/JG beta relaxation
- Density Scaling and Decoupling in o-Terphenyl, Salol, and Dibutyphthalate
- Improved Correlation for Viscosity from Surface Tension Data for Saturated Normal Fluids
- Activation Volume in the Density Scaling Regime: Equation of State and Its Test by Using Experimental and Simulation Data
- Empirical correlation of the surface tension versus the viscosity for saturated normal liquids
- Combined Description of Pressure-Volume-Temperature and Dielectric Relaxation of Several Polymeric and Low-Molecular-Weight Organic Glass-Formers using 'SL-TS2' Mean-Field Approach
- Virial-potential energy correlation and its relation to the density scaling for quasi-real model systems
- On the experimental determination of the repulsive component of the potential from high pressure measurements: what is special about twelve?
- Understanding Dynamics in Coarse-Grained Models: IV. Connection of Fine-Grained and Coarse-Grained Dynamics with the Stokes-Einstein and Stokes-Einstein-Debye Relations
- The origin of the density scaling exponent for polyatomic molecules and the estimation of its value from the liquid structure
- Generally applicable physics-based equation of state for liquids