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.

We simulate the continuous cooling processes of a single-component metallic model liquid with the molecular dynamics method in order to reexamine the claim [K. Shinjo, J. Chem. Phys. 90, 6627 (1989)] that the liquid–glass transition cannot be simulated with the method, i.e., the volume versus temperature relationship does not show a sharp or broad break but shows a meniscus curve in the continuous cooling processes. A sharp break means that the volume decreases linearly on both sides of the glass transition temperature. A broad break means that the volume decreases continuously in the intermediate temperature region although it changes linearly at both the sides. A meniscus curve means that the volume decreases continuously taking the shape of a bow. We analyze the structure of the continuously cooled state with the pair-distribution function and Voronoi polyhedron analysis. We find that the glass state can be formed even in the continuously cooled processes and even when the potential energy versus temperature curve shows a meniscus shape. We also find that a sharp break appears in the potential versus temperature curve in the continuous cooling process when the liquid is cooled slowly enough. The number of icosahedral clusters increases from just below the melting temperature and appears to saturate at a temperature below the break that corresponds to the conventional glass transition. The number of such clusters