What is Liquid? [in two dimensions]

• Autorzy: Travis K. P. , Hoover Wm. G. , Hoover C. G. , Hass A. B.

Identyfikatory

DOI

10.12921/cmst.2021.0000009

• Języki publikacji: EN

Abstrakty

EN

We consider the practicalities of defining, simulating, and characterizing “Liquids” from a pedagogical standpoint based on atomistic computer simulations. For simplicity and clarity we study two-dimensional systems throughout. In addition to the infinite-ranged Lennard-Jones 12/6 potential we consider two shorter-ranged families of pair potentials. At zero pressure one of them includes just nearest neighbors. The other longer-ranged family includes twelve additional neighbors. We find that these further neighbors can help stabilize the liquid phase. What about liquids? To implement Wikipedia’s definition of liquids as conforming to their container we begin by formulating and imposing smooth-container boundary conditions. To encourage conformation further we add a vertical gravitational field. Gravity helps stabilize the relatively vague liquid-gas interface. Gravity reduces the messiness associated with the curiously-named “spinodal” (tensile) portion of the phase diagram. Our simulations are mainly isothermal. We control the kinetic temperature with Nosé-Hoover thermostating, extracting or injecting heat so as to impose a mean kinetic temperature over time. Our simulations stabilizing density gradients and the temperature provide critical-point estimates fully consistent with previous efforts from free energy and Gibbs ensemble simulations. This agreement validates our approach.

Słowa kluczowe

EN

liquids; statistical physics; molecular dynamics; tension; spinodal; phase equilibria

• Wydawca: Institute of Bioorganic Chemistry Scientific Publishers OWN, Polish Academy of Sciences
• Czasopismo: Computational Methods in Science and Technology
• Rocznik: 2021
• Tom: Vol. 27, No. 1
• Strony: 5--23
• Opis fizyczny: Bibliogr.24 poz., rys.

Twórcy

autor

Travis K. P.

• Department of Materials Science & Engineering The University of Sheffield Sheffield S1 3JD, United Kingdom

autor

Hoover Wm. G.

• Ruby Valley Research Institute 601 Highway Contract 60 Ruby Valley, Nevada 89833, USA

autor

Hoover C. G.

• Ruby Valley Research Institute 601 Highway Contract 60 Ruby Valley, Nevada 89833, USA

autor

Hass A. B.

• Department of Applied Maths University of Leeds Leeds LS2 9JT, United Kingdom

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021).