Binary icosahedral quasicrystals of hard spheres in spherical confinement

Abstract

The influence of geometry on the local and global packing of particles is important to many fundamental and applied research themes such as the structure and stability of liquids, crystals and glasses. Here, weshow by experiments and simulations that a binary mixture of hard-sphere-like particles crystallizing into the MgZn 2 Laves phase in bulk, spontaneously forms 3D icosahedral quasicrystals in slowly drying droplets. Moreover, the local symmetry of 70-80% of the particles changes to that of the MgCu 2 Laves phase. Both of these findings are significant for photonic applications. If the stoichiometry deviates from that of the Laves phase, our experiments show that the crystallization of MgZn 2 is hardly affected by the spherical confinement. Our simulations show that the quasicrystals nucleate away from the spherical boundary and grow along five-fold symmetric structures. Our findings not only open the way for particle-level studies of nucleation and growth of 3D quasicrystals, but also of binary crystallization.

Tuning the Glass Transition: Enhanced Crystallization of the Laves Phases in Nearly Hard Spheres

“…11 In this work, we set the diameter ratio q = σ S /σ L = 0.78, which is close to the value of a recent experimental study. 20 Here σ α denotes the diameter of species α and σ σ σ = +…”

A rare event

“…For a BHS mixture, LPs are thermodynamically stable for a diameter ratio q ∈ [0.76, 0.84] [9]. In this Chapter, we set the diameter ratio q = σ S /σ L = 0.78, which is close to the value of a recent experimental study [76]. Here σ α denotes the diameter of species α and σ αβ = (σ α + σ β ) /2.…”