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We study the icosahedral clustering process in a supercooled single-component metal liquid by use of Voronoi polyhedron analysis. The number of the cluster increases with decreasing temperature from just below the melting temperature. The life of the cluster increases with decreasing temperature from slightly above the glass transition temperature Tg. The atoms with 0.56 fraction in the system become the central atoms of the cluster at least one time during the cooling process, although the total fraction of the clusters is 0.04 at temperatures far below the Tg. After atoms become the central atoms for the first time which we call fresh atoms, the atoms become central atoms of the other types of clusters, and after then revive as the central atoms of the icosahedral cluster. The life is longer for the revived atoms than for the fresh atoms in the low temperature region. The longer life is due to the energetic stability of the coordinate atoms around the revived atoms. We present atomistic transition processes from the cluster to the other types of clusters.

Glass formation and crystallization of liquid and glass rubidium: A constantpressure moleculardynamics study Defects and fluorine diffusion in sodium fluoroberyllate glass: A molecular dynamics study J. Chem. Phys. 75, 3516 (1981); 10.1063/1.442461 ESR and Mössbauer studies of crystallization process of sodium iron silicate glass Crystallization and glass formation processes are studied for the sodium system with 108 atoms by means of molecular dynamics simulation with constant volume. The equilibrium liquids, with four different initial conditions, are cooled with four different rates. The processes are analyzed by means of Voronoi polyhedra, diffusion coefficients, pair-distribution functions, and mean-square displacements. Embryo formation process, being accompanied by the abrupt slope increment of the displacement, appears with incubation period prior to nucleation and growth processes. The temperatures for the embryo formation and crystallization decrease with increasing cooling rate. The diffusion mechanism in supercooled liquid before the embryo formation is the same as that in equilibrium liquid. The critical cooling rate, which separates glass formation and crystallization processes, is greater than 8.00 X 1013 K S -1.

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