Kinetic coefficient for hard-sphere crystal growth from the melt.
نویسندگان
چکیده
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 mu100 = 1.44(7), mu110 = 1.10(5), and mu111 = 0.64(3) in units of square root (kB/(mTm)), where kB is Boltzmann's constant, m is the particle mass, and Tm 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 square root (R/(MTm)), where R is the gas constant, M is the molar mass, and C is a constant that varies with interfacial orientation.
منابع مشابه
Simulations of binary hard-sphere crystal-melt interfaces: interface between a one-component fcc crystal and a binary fluid mixture
The crystal-melt interfaces of a binary hard-sphere fluid mixture in coexistence with a single-component hard-sphere crystal is investigated using molecular-dynamics simulation. In the system under study, the fluid phase consists of a two-component mixture of hard spheres of differing size, with a size ratio α = 0.414. At low pressures this fluid coexists with a pure fcc crystal of the larger p...
متن کاملAnisotropic interfacial free energies of the hard-sphere crystal-melt interfaces.
We present a reliable method to define the interfacial particles for determining the crystal-melt interface position, which is the key step for the crystal-melt interfacial free energy calculations using capillary wave approach. Using this method, we have calculated the free energies gamma of the fcc crystal-melt interfaces for the hard-sphere system as a function of crystal orientations by exa...
متن کاملبررسی گذار فاز مایع - جامد با استفاده از نظریه تابعی چگالی وزنی اصلاح شده مایعات کلاسیک غیر یکنواخت با مولکولهای کروی سخت
In this article we first introduce the weighted density approximation (WDA) to study the classical inhomogeneous system such as inhomogeneous fluids. Then we introduce the modified weighted density approximation (MWDA) to calculate the structure and thermodynamical properties of the FCC hard sphere crystal. The MWDA is a self consistent method where the free energy is expressed as an unperturb...
متن کاملFundamental-measure density functional theory study of the crystal-melt interface of the hard sphere system.
Two versions of the fundamental measure density functionals together with a new interfacial density profile parametrization were used to study the hard-sphere crystal-melt interface in the framework of the fundamental measure density functional theory. The equilibrium interfacial density profiles and interfacial free energies were found as a result of minimization of grand canonical potential o...
متن کاملThree-dimensional numerical simulation of temperature and flow fields in a Czochralski growth of germanium
For a Czochralski growth of Ge crystal, thermal fields have been analysed numerically using the three-dimensional finite volume method (FLUENT package). The arrangement used in a real Czochralski crystal growth lab included a graphite crucible, heat shield, heating device, thermal insulation and chamber including two gas outlets. We have considered two cases for calculations, which are configur...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 97 21 شماره
صفحات -
تاریخ انتشار 2006