Formation of dodecagonal quasicrystals in two-dimensional systems of patchy particles

TL;DR

This study uses computer simulations to explore how two-dimensional patchy particles form various crystal and quasicrystal structures, revealing conditions under which dodecagonal quasicrystals emerge and their potential experimental realization.

Contribution

It demonstrates the formation of dodecagonal quasicrystals in 2D patchy particles and analyzes the conditions favoring their stability over other crystal forms.

Findings

Hexagonal crystals are stable at high pressure and wide patches.

Dodecagonal quasicrystals form near the stability boundary of hexagonal crystals.

Quasicrystals are stabilized by configurational entropy from tilings of squares and triangles.

Abstract

The behaviour of two-dimensional patchy particles with 5 and 7 regularly-arranged patches is investigated by computer simulation. For higher pressures and wider patch widths, hexagonal crystals have the lowest enthalpy, whereas at lower pressures and for narrower patches, lower-density crystals with five nearest neighbours and that are based on the (3^2,4,3,4) tiling of squares and triangles become lower in enthalpy. Interestingly, in regions of parameter space near to that where the hexagonal crystals become stable, quasicrystalline structures with dodecagonal symmetry form on cooling from high temperature. These quasicrystals can be considered as tilings of squares and triangles, and are probably stabilized by the large configurational entropy associated with all the different possible such tilings. The potential for experimentally realizing such structures using DNA multi-arm motifs are discussed.