147 Atomlu Co-Pd Nanoalaşımlarının Erime Dinamiği

Yıl 2016, Cilt: 6 Sayı: 2, 369 - 376, 01.06.2016

Ali Kemal Garip

Öz

Bu çalışmada, gaz fazındaki 147 atomlu Co-Pd nanoalaşımlarının teorik bir çalışması, atomlar arası etkileşmeler Gupta çok cisim potansiyel enerji fonksiyonu ile modellenerek yapılmıştır. ComPdn m+n=147 nanoalaşımlarının bazı kompozisyonları için en düşük enerjili yapılar Basin Hopping optimizasyon metodu ile elde edilmiştir. Tüm kompozisyonlar için m=0, 1, 13, 55, 92, 134, 147 ikosahedron geometrisi belirlenmiştir. Co13Pdçalışmada aynı zamanda Co-Pd nanoalaşımlarının iç ve kabuk katmanlarını da içeren erime dinamiği incelendi. Genel olarak erimenin en dıştaki kabuktan başladığı sonucu elde edildi

Anahtar Kelimeler

Erime, İç-kabuk, Nanoalaşım, Optimizasyon, Topak

Melting Dynamics of 147 Atom Co-Pd Nanoalloys

Öz

A theoretical study has been made of 147 atom Co-Pd nanoalloy clusters in gas phase, with the interatomic interactions modelled by Gupta many-body potential. Basin Hopping algorithm has been used to find the lowest energy structures for some compositions of ComPdn m+n=147 clusters. Icosahedron geometry has beenidentified for all compositions m=0, 1, 13, 55, 92, 134, 147 . Co13Pd134 nanoalloy has the highest melting point among for all these compositions. It’s also investigated the melting dynamics including core and shell layers of Co-Pd clusters in this study. It’s concluded that melting begins from outermost shell generally

Anahtar Kelimeler

Nanoalaşım, Optimizasyon, Topak, Erime, İç-kabuk

Kaynakça

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