Incipient triple point for adsorbed xenon monolayers: Pt(111) versus graphite substrates

TL;DR

This study uses molecular dynamics simulations to reveal an incipient triple point for xenon monolayers on platinum (111), contrasting with the normal triple point observed on graphite, highlighting substrate-dependent phase behaviors.

Contribution

It provides the first simulation evidence of an incipient triple point for xenon on Pt(111), differing from the well-known triple point on graphite surfaces.

Findings

Incipient triple point for xenon on Pt(111) at 120-150 K

Normal triple point for xenon on graphite at about 100 K

Surface substrate significantly influences phase transition behavior

Abstract

Simulation evidence of an incipient triple point is reported for xenon submonolayers adsorbed on the (111) surface of platinum. This is in stark contrast to the "normal" triple point found in simulations and experiments for xenon on the basal plane surface of graphite. The motions of the atoms in the surface plane are treated with standard 2D "NVE" molecular dynamics simulations using modern interactions. The simulation evidence strongly suggests an incipient triple point in the 120-150 K range for adsorption on the Pt (111) surface while the adsorption on graphite shows a normal triple point at about 100 K.