Stability of a hard-sphere binary quasicrystal

TL;DR

This paper investigates the stability of a binary hard-sphere quasicrystal using density-functional theory, revealing it is metastable at certain size ratios and stable at others, depending on the diameter ratio.

Contribution

It provides a theoretical analysis of quasicrystal stability in binary hard-sphere mixtures, extending understanding beyond previous molecular dynamics simulations.

Findings

Quasicrystal is metastable for diameter ratios above 0.83.

At lower diameter ratios, the quasicrystal becomes stable relative to the crystal.

The quasicrystal does not reach coexistence with the fluid phase at lower ratios.

Abstract

The stability of a quasicrystalline structure, recently obtained in a molecular-dynamics simulation of rapid cooling of a binary melt, is analyzed for binary hard-sphere mixtures within a density-functional approach. It is found that this quasicrystal is metastable relative to crystalline and fluid phases for diameter ratios above 0.83. Such trend is partially reversed for lower diameter ratios, since the quasicrystal becomes stable with respect to the crystal but does not reach a coexistence with the fluid.