Quantum mechanics

Icosahedral symmetry

Phase (matter)

Chemical physics

SPHERES

Nanoparticle

Materials science

Intermetallic

Laves phase

Computer science

Geology

Oceanography

Thermodynamics

Physics

Nanotechnology

Crystallization

Alloy

Quasicrystal

Cluster (spacecraft)

Mathematics

Astronomy

Molecular physics

Condensed matter physics

Particle (ecology)

Composite material

Crystallography

Chemistry

Programming language

Nucleation

Binary number

Hard spheres

Arithmetic

Nature Physics

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, we show by experiments and simulations that a binary mixture of hard-sphere-like particles crystallizing into the MgZn2 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 MgCu2 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 MgZn2 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.

Binary icosahedral clusters of hard spheres in spherical confinement