Molecular Dynamics Simulations of Metastable States of Repulsive Soft Spheres

• Published in: Journal of the Physical Society of Japan Vol. 93; no. 10; p. 1
• Main Author: Aoki, Keiko M.
• Format: Journal Article
• Language: English
• Published: Tokyo The Physical Society of Japan 15-10-2024
• Subjects: Distribution functions; Elastic analysis; Elastic limit; Elastic properties; Liquid phases; Metastable state; Molecular dynamics; Phase transitions; Structural analysis; Temperature; Thermodynamic equilibrium; Thermodynamics; Transition temperature
• ISSN: 0031-9015; 1347-4073
• DOI: 10.7566/JPSJ.93.104004

Metastable states of repulsive soft spheres interacting through Weeks–Chandler–Andersen potential are simulated by deterministic isobaric-isothermal molecular dynamics simulations. These metastable states exist at certain temperature ranges below the crystal-liquid phase transition temperature Tc−l. The liquid state above Tc−l is extrapolated to the most diffusive metastable state (usually called supercooled liquid) below its transition temperature. Other metastable states transform to the most diffusive metastable state at some temperature below Tc−l. The scaling relations hold not only for the thermodynamic equilibrium states but also for the metastable states. The focus is on a state with the 2nd largest diffusivity (called state D) which only exists for a limited range of temperature. This state transforms to the most diffusive metastable state at higher temperatures below Tc−l, and stepwise to less diffusive states at lower temperatures. Thermodynamic quantities as well as dynamic and elastic properties are reported. Structural analysis of this peculiar state has revealed that the medium range of the pair distribution function have a specific characteristic.