Probing the link between residual entropy and viscosity of molecular fluids and model potentials

Bell, Ian H.

doi:10.1073/pnas.1815943116

Cited by 70 publications

(66 citation statements)

References 99 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since then, the number of simulations for the Lennard-Jones 12-6 fluid has increased dramatically, due to the popular approach of modeling the thermodynamic and transport properties of real fluids by analogy with the Lennard-Jones 12-6 fluid. 2,8 Here, in this work, we have collected the most comprehensive set of transport data for the Lennard-Jones 12-6 fluid from the literature and applied a novel scaling approach that is based on approaches proposed by Rosenfeld. 1,9 Following the approach of ref 2, we use referencequality thermodynamic models in order to minimize the uncertainty in excess entropy.…”

Section: Introductionmentioning

confidence: 99%

Modified Entropy Scaling of the Transport Properties of the Lennard-Jones Fluid

et al. 2019

Self Cite

View full text Add to dashboard Cite

Rosenfeld proposed two different scaling approaches to model the transport properties of fluids, separated by 22 years, one valid in the dilute gas, and another in the liquid phase. In this work, we demonstrate that these two limiting cases can be connected through the use of a novel approach to scaling transport properties and a bridging function. This approach, which is empirical and not derived from theory, is used to generate reference correlations for the transport properties of the Lennard-Jones 12-6 fluid of viscosity, thermal conductivity, and self-diffusion. This approach, with a very simple functional form, allows for the reproduction of the most accurate simulation data to within nearly their statistical uncertainty. The correlations are used to confirm that for the Lennard-Jones fluid the appropriately scaled transport properties are nearly monovariate functions of the excess entropy from low-density gases into the supercooled phase and up to extreme temperatures. This study represents the most comprehensive metastudy of the transport properties of the Lennard-Jones fluid to date.

show abstract

Section: Introductionmentioning

confidence: 99%

Modified Entropy Scaling of the Transport Properties of the Lennard-Jones Fluid

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…The work of Rosenfeld 4 ambitiously posited, based on the minimal molecular dynamics data available at the time, a universal relationship between the macroscopically scaled viscosity (a transport property) and the residual entropy (an equilibrium thermodynamic property) for atomic liquids; this universal relationship does not hold for molecular fluids. 5 The macroscopically reduced viscosity is defined by where η is the shear viscosity, ρ N is the number density (the number of particles per unit volume), m is the mass of one particle, k B is the Boltzmann constant, and T is the temperature. In the case of atomic fluids (Rosenfeld's focus), the dimensional scales are those of the liquid phase (length: ρ N −1/3 , energy: k B T, time:…”

Section: Introductionmentioning

confidence: 99%

Entropy Scaling of Viscosity—II: Predictive Scheme for Normal Alkanes

Bell

2020

J. Chem. Eng. Data

Self Cite

View full text Add to dashboard Cite

In this work, a residual entropy value of 6/10 of the way between the critical point and a value of −2/3 of Boltzmann constant is shown to collapse the scaled viscosity for the family of normal alkanes. Based on this approach, a nearly universal correlation is proposed that can reproduce 95% of the experimental data for normal alkanes within ±18% (without removal of clearly erroneous data). This universal correlation has no new fluid-specific empirical parameters and is based on experimentally accessible values. This collapse is shown to be valid to a residual entropy half-way between the critical point and the triple point, beyond which the macroscopically scaled viscosity has a superexponential dependence on residual entropy, terminating at the triple point. A key outcome of this study is a better understanding of entropy scaling for fluids with intramolecular degrees of freedom. A study of the transport and thermodynamic properties at the triple point rounds out the analysis.

show abstract

“…Here, "ex" refer to the entropy in excess of the ideal gas entropy: S ex = S −S id . This scaling with excess entropy was first suggested by Rosendeld in 1977 [22], but have recently gained renewed interest [23][24][25][26][27]. A configurational adiabat is only referred to as an isomorph for state-points with hidden scale-invariance and thus invariant structure (iso-morf is the greek word for same-shape).…”

Section: Hidden Scale Invariancementioning

confidence: 93%

Solid-liquid coexistence of the noble elements. I. Theory illustrated by the case of argon

Singh,

Dyre,

Pedersen

2020

Preprint

View full text Add to dashboard Cite

The noble elements constitute the simplest group of atoms. At low temperatures or high pressures they freeze into the face-centered cubic (fcc) crystal structure (except helium). We perform molecular dynamics using the recently proposed simplified ab initio atomic (SAAP) potential [Deiters and Sadus, J. Chem. Phys. 150, 134504 (2019)] . This potential is parameterized using data from accurate ab initio quantum mechanical calculations by the coupled-cluster approach on the CCSD(T) level. We compute the fcc freezing lines for Argon and find a great agreement with the experimental values. At low pressures, this agreement is further enhanced by using many-body corrections.Hidden scale invariance of the potential energy function is validated by computing lines of constant excess entropy (configurational adiabats) and shows that mean square displacement and the static structure factor are invariant. These lines (isomorphs) can be generated from simulations at a single state-point by having knowledge of the pair potential. The isomorph theory for the solid-liquid transition is used to accurately predict the shape of the freezing line in the pressure-temperature plane, the shape in the density-temperature plane, the entropy of melting and the Lindemann parameters along the melting line. We finally predict that the body-centered cubic (bcc) crystal is stable at high pressures.

show abstract

Probing the link between residual entropy and viscosity of molecular fluids and model potentials

Cited by 70 publications

References 99 publications

Modified Entropy Scaling of the Transport Properties of the Lennard-Jones Fluid

Modified Entropy Scaling of the Transport Properties of the Lennard-Jones Fluid

Entropy Scaling of Viscosity—II: Predictive Scheme for Normal Alkanes

Solid-liquid coexistence of the noble elements. I. Theory illustrated by the case of argon

Contact Info

Product

Resources

About