Sihirli Sayı Davranışı Gösteren Cu, Pd ve Ti Metal Kümelerinin Katı-Sıvı Faz Geçişleri

Yıl 2016, Cilt: 6 Sayı: 1, 174 - 181, 01.01.2016

Meral Eryürek

Öz

Çok cisim Gupta potansiyelinin kullanıldığı mikrokanonik Moleküler Dinamik MD yöntemi ile Cu, Pd ve Ti metal atomlarının sihirli sayı kümelerinin erime özellikleri incelenmiştir. Çoklu histogram yöntemi kullanılarak termodinamik nicelikler hesaplanmıştır. Kalorik eğriler, bağ uzunluğundaki dalgalanmaların kare ortalamasının karekökü δrms , konfigurasyonel entropi, ısı kapasitesi ve potansiyel enerji dağılım eğrileri elde edilmiştir. Bu niceliklerden yararlanılarak erime sıcaklıkları ve erime davranışının geometriye bağlılığı belirlenmiştir. Potansiyel enerji dağılımlarının, kümelerin erime davranışlarını belirlemekte kritik rol alabileceği bulunmuştur

Anahtar Kelimeler

Atomik Küme, Sihirli Sayı, Erime, Isı Kapasitesi, MD, Histogram Yöntemi

The Solid-Liquid Phase Transitions of Magic Numbers of Metal Clusters: Cu, Pd and Ti

Öz

The melting properties of Cu, Pd and Ti Metal clusters magic numbers geometries were simulated by a micro-canonical molecular dynamics method using Gupta many body potential. Their thermodynamic quantities were calculated by using multiple histogram method. The caloric curves and, relative root-mean square rms bond length fluctuation, configurational entropy, heat capacity and potential energy distributions graphs were evaluated. The dependence of these quantities on the geometries of the clusters was examined, melting temperatures was determined and it is found that potential energy distribution is the key quantity to determine the melting type.

Anahtar Kelimeler

Atomic cluster, Magic number, Melting, Heat Capacity, MD, Histogram methods.

Kaynakça

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