Testing of Frank's hypothesis on a containerless packing of macroscopic soft spheres and comparison with mono-atomic metallic liquids

It is well-known that metallic liquids can exist below their equilibrium melting temperature for a considerable time. To explain this, Frank [1] proposed that icosahedral ordering, incompatible with crystalline long-range order, is prevalent in the atomic structure of these liquids, stabilizing them and enabling them to be supercooled. Some studies of the atomic structures of metallic liquids using Beam-line Electrostatic Levitation (BESL; containerless melting), and other techniques, support this hypothesis [2] and [3]. Here we examine Frank's hypothesis in a system of macroscopic, monodisperse deformable spheres obtained by containerless packing under the influence of centripetal force. The local structure of this packing is analyzed and compared with atomic ensembles of liquid transition metals obtained by containerless melting using the BESL method.

► Testing of Frank's hypothesis for Centripetal Packing (CP) has been proposed.
► It is shown that CP is an idealized model for Monatomic Supercooled Liquid (MSL).
► The CP is fit for comparing with studies on MSL in a containerless environment.
► We measure local orders in CP by HA and BOO methods for the first time.
► It is shown that icosahedral order is greater in CP than MSL and reasons explored.