L12 fazda Rh3La bileşiğinin ab inito çalışması

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

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.

Keywords:

DFT, band structure, elastic constant, phonon,

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