Two-temperature-region model for cluster-growth simulations: formulation and application to the growth of fcc 201-atom Lennard-Jones clusters
Artykuł w czasopiśmie
| Status: | |
| Autorzy: | Polak Wiesław |
| Rok wydania: | 2005 |
| Wersja dokumentu: | Drukowana | Elektroniczna |
| Język: | angielski |
| Numer czasopisma: | 23 |
| Wolumen/Tom: | 71 |
| Numer artykułu: | 235413 |
| Impact Factor: | 3,185 |
| Web of Science® Times Cited: | 5 |
| Scopus® Cytowania: | 6 |
| Bazy: | Web of Science | Scopus |
| Efekt badań statutowych | NIE |
| Materiał konferencyjny: | NIE |
| Publikacja OA: | NIE |
| Abstrakty: | angielski |
| The growth of Lennard-Jones clusters was simulated using a specially developed technique based on applying the Monte Carlo method and distinguishing two regions (nucleus and vapor) of two different temperatures. Cluster growth was initiated from a 201-atom cluster in the truncated octahedron form of initially perfect fcc structure and ended when the cluster was composed of ca. 2000 atoms. Three reduced temperatures T-n(*)=0.25, 0.30, and 0.35 as well as four different atom concentrations in the vapor region were analyzed to find parameters enabling a good atom ordering in the growing cluster. The simulations revealed that at sufficiently slow growth the clusters are very well arranged with the order parameter in the range from 91% to 98% depending on the temperature. However, all growth simulations always lead to the formation of hcp planes on some (111) dense-packed cluster planes due to a misfit in the position of newly added atoms resulting in ...ABCABA instead of ...ABCABC layer sequence. The subsequent growth of the created hcp layer can lead to the enlargement of this layer or to the formation of an fcc plane over the existing hcp one in the process of kinetic trapping. As observed in the simulations, two hcp planes crossing at an angle close to 70.53 degrees usually form a linear chain of decahedral local structures in the contact region. This mechanism transforms a defected crystalline cluster to a noncrystalline one. |
