Kinetic coefficient for hard-sphere crystal growth from the melt

Abstract

Using molecular-dynamics simulation, we determine the magnitude and anisotropy of the kinetic coefficient (mu) for the crystal growth from the melt for the hard-sphere system through an analysis of equilibrium capillary fluctuations in interfacial height. We find mu(100)=1.44(7), mu(110)=1.10(5), and mu(111)=0.64(3) in units of root k(B)/(mT(m)), where k(B) is Boltzmann's constant, m is the particle mass, and T-m is the melting temperature. These values are shown to be consistent, with some exceptions, with those obtained in recent simulation results a variety of fcc metals, when expressed in hard-sphere units. This suggests that the kinetic coefficient for fcc metals can be roughly estimated from C root R/(MTm), where R is the gas constant, M is the molar mass, and C is a constant that varies with interfacial orientation.