Solid-liquid surface free energy of Lennard-Jones liquid on smooth and rough surfaces computed by molecular dynamics using the phantom-wall method

An important feature in the design of superhydrophobic surfaces is their robustness against collapse from the Cassie–Baxter configuration to the Wenzel state. Upon such a transition a surface loses its properties of low adhesion and friction. We describe how to adapt the Surface Evolver algorithm to predict the parameters and mechanism of the collapse transition on posts of arbitrary shape. In particular, contributions to the free energy evaluated over the solid–liquid surface are reduced to line integrals to give good convergence. The algorithm is validated for straight, vertical and inclined, posts. Numerical results for curved posts with a horizontal section at their ends show that these are more efficient in stabilizing the Cassie state than straight posts, and identify whether the interface first depins from the post sides or the post tips.

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A variational approach to nucleation simulation

Faraday Discussions ◽

10.1039/c6fd00127k ◽

2016 ◽

Vol 195 ◽

pp. 557-568 ◽

Cited By ~ 12

Author(s):

Pablo M. Piaggi ◽

Omar Valsson ◽

Michele Parrinello

Keyword(s):

Molecular Dynamics ◽

Computer Simulation ◽

Free Energy ◽

Variational Approach ◽

Sampling Method ◽

Enhanced Sampling ◽

Technical Problems ◽

Lennard Jones ◽

Dynamics Simulations

We study by computer simulation the nucleation of a supersaturated Lennard-Jones vapor into the liquid phase. The large free energy barriers to transition make the time scale of this process impossible to study by ordinary molecular dynamics simulations. Therefore we use a recently developed enhanced sampling method [Valsson and Parrinello, Phys. Rev. Lett.113, 090601 (2014)] based on the variational determination of a bias potential. We differ from previous applications of this method in that the bias is constructed on the basis of the physical model provided by the classical theory of nucleation. We examine the technical problems associated with this approach. Our results are very satisfactory and will pave the way for calculating the nucleation rates in many systems.

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Molecular dynamics and higher-order perturbation-theory results for the anharmonic free energy and equation of state of a Lennard-Jones solid

Physical Review B ◽

10.1103/physrevb.54.3266 ◽

1996 ◽

Vol 54 (5) ◽

pp. 3266-3272 ◽

Cited By ~ 17

Author(s):

Daniel J. Lacks ◽

Ramesh C. Shukla

Keyword(s):

Molecular Dynamics ◽

Free Energy ◽

Perturbation Theory ◽

Equation Of State ◽

Higher Order ◽

Order Perturbation ◽

Order Perturbation Theory ◽

Lennard Jones

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COMPARISON BETWEEN MOLECULAR DYNAMICS AND MONTE CARLO DESCRIPTIONS OF SOLID–LIQUID PHASE-TRANSITION OF LENNARD–JONES FLUIDS

International Journal of Modern Physics C ◽

10.1142/s0129183110015154 ◽

2010 ◽

Vol 21 (03) ◽

pp. 349-363 ◽

Cited By ~ 1

Author(s):

A. S. MARTINS ◽

C. X. S. SEIXAS ◽

L. B. dos SANTOS ◽

P. R. RIOS

Keyword(s):

Phase Transition ◽

Molecular Dynamics ◽

Monte Carlo ◽

Liquid Phase ◽

Structural Evolution ◽

Liquid Phase Transition ◽

Monte Carlo Techniques ◽

Lennard Jones ◽

Liquid Transition ◽

Solid Liquid

Molecular dynamics and Monte Carlo techniques are employed for the study of Lennard–Jones fluids near the solid–liquid transition region. Systematic comparisons between the predictions of both techniques are discussed, with particular emphasis on the structural evolution and location of the transition (melting) temperature Tm.

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