L12 fazda Rh3La bileşiğinin ab inito çalışması

Yıl 2016, Cilt: 20 Sayı: 3, 591 - 595, 02.09.2016

Osman Örnek

https://doi.org/10.16984/saufenbilder.44024

Cited By: 2

Öz

Rh₃La bileşiğinin yapısal, elastik, elektronik ve fonon özelliklerini yoğunluk fonksiyonel teorisi ile incelenmiştir. Bu bileşiğin hesaplanan örgü sabiti eldeki veri ile uyum içindedir. Rh₃La bileşiği için L1₂ fazda ki elastik sabitleri (C₁₁, C₁₂ ve C₄₄) enerji-strain metodu kullanılarak hesaplanmıştır. Bu elastik sabitleri mekanik kararlılık şartlarını karşılıyor ve Rh₃La bileşiğinin sünekliği Pugh kriterleri tarafından doğrulanmıştır. L1₂-Rh₃La bileşiğinin sunulan elektronik bant yapısı metalik karaktere sahip olduğunu göstermiştir. Bu bileşiği fonon özellikleri yoğunluk fonksiyonel pertürbasyon terorisi kullanılarak elde edilmiştir. Son olarak, sıcaklığa karşı sabit hacimde ısı sığası yarı-harmonik yaklaşımı kullanılarak hesaplandı ve tartışıldı.

Anahtar Kelimeler

DFT, band yapısı, elastik sabiti, fonon

Ab inito study of Rh3La compound in L12 phase

Öz

The structural, elastic, electronic and phonon properties of Rh₃La compound within density functional theory have been investigated. The calculated lattice constant for this compound is in good agreement with the available data. The elastic constants (C₁₁, C₁₂ and C₄₄) in L1₂ phase for Rh₃La compound are calculated using the energy-strain method. These calculated elastic constants satisfy the mechanical stability criterion and the ductility of Rh₃La is predicted by Pugh’s criterion. The present electronic band structure calculations predict that the L1₂-Rh₃La compound has metallic characters. Phonon properties of this compound have been obtained using the density-functional perturbation theory. Finally specific heat at constant volume versus temperature is calculated and discussed using the quasi harmonic approximation.  

Anahtar Kelimeler

DFT, band structure, elastic constant, phonon

Kaynakça

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