Universal Two-Component Dynamics in Supercritical Fluids.

ABSTRACT: Despite the technological importance of supercritical fluids, controversy remains about the details of their microscopic dynamics. In this work, we study four supercritical fluid systems─water, Si, Te, and Lennard-Jones fluid─via classical molecular dynamics simulations. A universal two-component behavior is observed in the intermolecular dynamics of these systems, and the changing ratio between the two components leads to a crossover from liquidlike to gaslike dynamics, most rapidly around the Widom line. We find evidence to connect the liquidlike component dominating at lower temperatures with intermolecular bonding and the component prominent at higher temperatures with free-particle, gaslike dynamics. The ratio between the components can be used to describe important properties of the

SUBMITTER: Sun P 

PROVIDER: S-EPMC8686117 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature