Numerical calculation of the rate of crystal nucleation in a Lennard‐Jones system at moderate undercooling

We report a computer‐simulation study of the rate of homogeneous crystal nucleation and the structure of crystal nuclei in a Lennard‐Jones system at moderate undercooling. The height of the nucleation barrier has been determined using umbrella sampling, whereas the barrier crossing rate is calculated using molecular dynamics simulation. The simulations clearly show that the barrier crossing is a diffusive process. Nevertheless, the kinetic prefactor in the nucleation rate is found to be some two orders of magnitude larger than predicted by classical nucleation theory. The height of the barrier is in good agreement with the theoretical prediction. Although the Lennard‐Jones system has a stable face‐centered cubic (fcc) phase below the melting line, the precritical nuclei are found to be mainly body‐centered cubic (bcc) ordered. As they grow to their critical size, they become more fcc ordered in the core. However, the critical and postcritical nuclei retain a high degree of bcc ordering in the interface. F...

[1]  J. McTague,et al.  Should All Crystals Be bcc? Landau Theory of Solidification and Crystal Nucleation , 1978 .

[2]  M. J. Ruiz-Montero,et al.  Numerical evidence for bcc ordering at the surface of a critical fcc nucleus. , 1995, Physical review letters.

[3]  D. Oxtoby,et al.  A molecular theory of crystal nucleation from the melt , 1984 .

[4]  David Turnbull,et al.  Rate of Nucleation in Condensed Systems , 1949 .

[5]  Boyer Ll,et al.  Statics and dynamics of icosahedrally twinned and single-crystal fcc clusters. , 1990 .

[6]  K. Kelton Crystal Nucleation in Liquids and Glasses , 1991 .

[7]  P. Steinhardt,et al.  Bond-orientational order in liquids and glasses , 1983 .

[8]  G. Torrie,et al.  Monte Carlo free energy estimates using non-Boltzmann sampling: Application to the sub-critical Lennard-Jones fluid , 1974 .

[9]  J. Q. Broughton,et al.  Crystallization of fcc (111) and (100) crystal‐melt interfaces: A comparison by molecular dynamics for the Lennard‐Jones system , 1988 .

[10]  G. Ciccotti,et al.  Constrained reaction coordinate dynamics for the simulation of rare events , 1989 .

[11]  J. Cape,et al.  AN ANALYSIS OF CRYSTALLIZATION BY HOMOGENEOUS NUCLEATION IN A 4000-ATOM SOFT-SPHERE MODEL , 1981 .

[12]  J. McTague,et al.  Crystal nucleation in a three‐dimensional Lennard‐Jones system: A molecular dynamics study , 1976 .

[13]  P. Clancy,et al.  The kinetics of crystal growth and dissolution from the melt in Lennard‐Jones systems , 1995 .

[14]  J. Banavar,et al.  Computer Simulation of Liquids , 1988 .

[15]  Jean-Pierre Hansen,et al.  Phase Transitions of the Lennard-Jones System , 1969 .

[16]  Aneesur Rahman,et al.  Interaction potentials and their effect on crystal nucleation and symmetry , 1979 .

[17]  S. Nosé,et al.  Isothermal–isobaric computer simulations of melting and crystallization of a Lennard‐Jones system , 1986 .

[18]  H. C. Andersen,et al.  Molecular dynamics study of melting and freezing of small Lennard-Jones clusters , 1987 .

[19]  Klein,et al.  Crystalline nucleation in deeply quenched liquids. , 1986, Physical review letters.

[20]  Andersen,et al.  10(6)-particle molecular-dynamics study of homogeneous nucleation of crystals in a supercooled atomic liquid. , 1990, Physical review. B, Condensed matter.

[21]  Alan C. Brown,et al.  Molecular dynamics investigation of homogeneous nucleation for inverse power potential liquids and for a modified Lennard‐Jones liquid , 1984 .

[22]  D. Herlach,et al.  Nucleation and metastable phase formation in undercooled FeCrNi melts , 1994 .

[23]  J. Farges,et al.  Noncrystalline structure of argon clusters. I. Polyicosahedral structure of ArN clusters, 20 , 1983 .

[24]  George H. Gilmer,et al.  Molecular dynamics investigation of the crystal–fluid interface. VI. Excess surface free energies of crystal–liquid systems , 1986 .

[25]  Tohru Ogawa,et al.  Geometrical Analysis of Crystallization of the Soft-Core Model*) , 1977 .

[26]  D. Oxtoby Homogeneous nucleation: theory and experiment , 1992 .

[27]  H. Kramers Brownian motion in a field of force and the diffusion model of chemical reactions , 1940 .

[28]  Yang,et al.  Molecular-dynamics investigation of deeply quenched liquids. , 1988, Physical review letters.

[29]  Aneesur Rahman,et al.  Crystal nucleation in a three‐dimensional Lennard‐Jones system. II. Nucleation kinetics for 256 and 500 particles , 1977 .

[30]  Samuel Glasstone,et al.  The Theory Of Rate Processes , 1941 .

[31]  Ralph E. Christoffersen,et al.  Algorithms for Chemical Computations , 1977 .

[32]  D. Chandler,et al.  Introduction To Modern Statistical Mechanics , 1987 .

[33]  B. W. V. D. Waal Stability of face‐centered cubic and icosahedral Lennard‐Jones clusters , 1989 .

[34]  J. Q. Broughton,et al.  Crystallization Rates of a Lennard-Jones Liquid , 1982 .

[35]  R. Eppenga,et al.  Monte Carlo study of the isotropic and nematic phases of infinitely thin hard platelets , 1984 .

[36]  David Chandler,et al.  Statistical mechanics of isomerization dynamics in liquids and the transition state approximation , 1978 .

[37]  W. Vos,et al.  Competition between vitrification and crystallization of methanol at high pressure , 1995 .

[38]  Daan Frenkel,et al.  COMPUTER-SIMULATION STUDY OF FREE-ENERGY BARRIERS IN CRYSTAL NUCLEATION , 1992 .

[39]  Carey K. Bagdassarian,et al.  Crystal nucleation and growth from the undercooled liquid: A nonclassical piecewise parabolic free‐energy model , 1994 .

[40]  H. C. Andersen,et al.  Small system size artifacts in the molecular dynamics simulation of homogeneous crystal nucleation in supercooled atomic liquids , 1986 .

[41]  A. Haymet Orientational environments in liquids and solids , 1984 .

[42]  Daan Frenkel,et al.  Free energy changes on freezing and melting ductile metals , 1993 .

[43]  T. Kelly,et al.  Solidification structures in submicron spheres of iron-nickel: Analytical evaluation☆ , 1988 .