Connecting Entropy Scaling and Density Scaling

Abstract

It is shown that the residual entropy (entropy minus that of the ideal gas at the same temperature and density) is mostly synonymous with the independent variable of density scaling, identifying a direct link between these two approaches. The two-body residual entropy is demonstrated to not be a suitable surrogate for the total residual entropy in the gas phase. The residual entropy and the effective hardness of interaction (itself a derivative at constant residual entropy) are studied for the Lennard-Jones monomer and dimer as well as a range of rigid molecular models for carbon dioxide. It is observed that the density scaling exponent is related to the two-body interactions.

References in corpus (16)

• "Isomorphs" in liquid state diagrams
• Pressure-energy correlations in liquids. IV. "Isomorphs" in liquid state diagrams
• Pressure-energy correlations in liquids. I. Results from computer simulations
• Strong pressure-energy correlations in van der Waals liquids
• Pressure-energy correlations in liquids. II. Analysis and consequences
• Beyond power-law density scaling: Theory, Simulation, and Experiment
• What constitutes a simple liquid?
• Probing the link between residual entropy and viscosity of molecular fluids and model potentials
• RUMD: A general purpose molecular dynamics package optimized to utilize GPU hardware down to a few thousand particles
• ms2: A molecular simulation tool for thermodynamic properties, new version release
• Hidden scale invariance of metals
• Experimental evidence of a state-point dependent scaling exponent of liquid dynamics
• Connection between dynamics and thermodynamics of liquids on the melting line
• Intermolecular distance and density scaling of dynamics in molecular liquids
• On the experimental determination of the repulsive component of the potential from high pressure measurements: what is special about twelve?
• Density scaling of generalized Lennard-Jones fluids in different dimensions