Melting of Hard Cubes

TL;DR

This paper investigates the melting behavior of hard cubes, revealing that freely rotating cubes melt via a first-order transition while parallel cubes undergo a continuous transition with distinct order loss, supported by defect-mediated theory.

Contribution

It provides a comparative analysis of melting transitions in hard cubes with different orientations, highlighting the role of particle rotation in the nature of the transition.

Findings

Freely rotating cubes melt through a first-order transition.

Parallel cubes exhibit a continuous melting transition.

Bond-orientational order persists after melting in parallel cubes.

Abstract

The melting transition of a system of hard cubes is studied numerically both in the case of freely rotating cubes and when there is a fixed orientation of the particles (parallel cubes). It is shown that freelly rotating cubes melt through a first-order transition, whereas parallel cubes have a continuous transition in which positional order is lost but bond-orientational order remains finite. This is interpreted in terms of a defect-mediated theory of melting