Thermodynamic and structural anomalies of the Gaussian-core model in one dimension

TL;DR

This study explores the unusual thermodynamic and structural behaviors of a one-dimensional Gaussian-core particle system, revealing anomalies similar to those in water despite lacking a phase transition.

Contribution

It provides new insights into the complex behaviors of bounded repulsive systems in one dimension, highlighting anomalies and structural regimes not previously characterized.

Findings

Presence of density and response function anomalies

Emergence of clustered crystal-like correlations under compression

Absence of a traditional fluid-solid phase transition

Abstract

We investigated the equilibrium properties of a one-dimensional system of classical particles which interact in pairs through a bounded repulsive potential with a Gaussian shape. Notwithstanding the absence of a proper fluid-solid phase transition, we found that the system exhibits a complex behaviour, with "anomalies" in the density and in the thermodynamic response functions which closely recall those observed in bulk and confined liquid water. We also discuss the emergence in the cold fluid under compression of an unusual structural regime, characterized by density correlations reminiscent of the ordered arrangements found in clustered crystals.