WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653
Browse
3 results
Search Results
Article Citation - WoS: 4Citation - Scopus: 4Phase Changes in Icosahedral 54-, 55-, 56-Atom Platinum Clusters(World Scientific Publ Co Pte Ltd, 2004) Güvenç, ZB; Kökten, H; Sebetci, AUsing the Voter and Chen version of an embedded-atom model, derived by fitting simultaneously to experimental data both the diatomic molecule and bulk platinum, we have studied the melting behavior of free, icosahedral, 54-, 55- and 56-atom platinum clusters in the molecular dynamics simulation technique. We present an atom-resolved analysis method that includes physical quantities such as the root-mean-square bond-length fluctuation and coordination number for individual atoms as functions of temperature. The effect of a central atom in the icosahedral structure to the melting process is discussed. The results show that the global minimum structures of the 54-, 55- and 56-atom Pt clusters do not melt at a specific temperature, rather, melting processes take place over a finite temperature range. The heat capacity peaks are not delta-functions, but instead remain finite. An ensemble of clusters in the melting region is a mixture of solid-like and liquid-like clusters.Article Citation - WoS: 7Citation - Scopus: 7Structure and Dynamical Properties of Aun, N=12-14 Clusters: Molecular Dynamics Simulation(World Scientific Publ Co Pte Ltd, 2005) Yildirim, EK; Atis, M; Güvenç, ZBUsing molecular dynamics and thermal quenching methods on the basis of Voter-Chen version of the embedded-atom method, we have studied the melting behavior of Au-N (N = 12, 13, 14) clusters. This behavior is described in terms of overall and atom resolved root-mean-square bond-length fluctuations, specific-heat, short- and long-time average coordination numbers of each atom and short-time average temperatures of the clusters. The isomer sampling probabilities are obtained from the thermal quenching of the molten clusters, and their energy-spectrum widths are investigated. Phase change of a cluster takes place with the collective and simultaneous motion of all the atoms.Article Citation - WoS: 3Citation - Scopus: 3Parallelization of a Molecular Dynamics Simulation of an Ion-Surface Collision(World Scientific Publ Co Pte Ltd, 2005) Özdogan, C; Güvenç, ZB; Atis, MParallel molecular dynamics simulation study of the ion-surface collision system is reported. A sequential molecular dynamics simulation program is converted into a parallel code utilizing the concept of parallel virtual machine (PVM). An effective and favorable algorithm is developed. Our parallelization of the algorithm shows that it is more efficient because of the optimal pair listing, linear scaling, and constant behavior of the internode communications. The code is tested in a distributed memory system consisting of a cluster of eight PCs that run under Linux (Debian 2.4.20 kernel). Our results on the collision system are discussed based on the speed up, efficiency and the system size. Furthermore, the code is used for a full simulation of the Ar-Ni(100) collision system and calculated physical quantities are presented.