The First Principles Approach to The Structural, Elastic, Electronic, Vibrational and Thermal Properties of CsCl type-ErAu Alloy

Lantanit-altın ikili alaşımları, dirence dayalı elektrik ölçüm teknolojilerinin uygulamalarında çok dikkat çekmektedir. Bu tür malzemeler, büyük sıcaklık kararlılığına bağlı olarak elektrik devreleri için uygun kabul edilir. Bu çalışmada, birim hücredeki ErAu ikili alaşımının iki atomlu CsCl-tipli kristal yapısının yapısal, elastik, elektronik, titreşimsel ve termal özellikleri ilk ilkeler yaklaşımı çerçevesinde incelenmiştir. Örgü parametresi 3.603 Å olarak bulunmuştur. Elde edilen yapısal parametreler mevcut çalışmalarla tutarlıdır. Elektronik özelliklerini göz önüne alındığında, elektronik bant yapıları, ErAu alaşımının toplam ve kısmi durumlarının yoğunluğu belirlenir. Bu hesaplamalardan, ErAu alaşımının metalik özellikte olduğu belirlenmiştir. Elastik sabitler, gerilme-zorlama yöntemi kullanılarak hesaplanmıştır. Elastik sabitler, farklı basınç değerleri için de elde edilmiştir. Sistemin elastik özellikleri ErAu alaşımının farklı basınç değerlerinde mekanik olarak dengeli olduğunu ortaya koymaktadır. Fonon frekansları hesaplanmıştır ve yapı dinamik olarak kararlı olarak belirlenmiştir. ErAu alaşımının termal özelliklerini sunmak için, sistemin serbest enerjisi, entropi ve ısı kapasitesi artan sıcaklık değerleri altında elde edilmiştir

ErAu Alaşımının Yapısal, Elastik, Elektronik, Titreşimsel ve Termal Özelliklerine İlk İlkeler Yaklaşımı

Lanthanide-gold binary alloys are very attracting attention in applications of electrical measuring technology based on resistance. Such materials are considered suitable for electrical circuits due to the large temperature stability. In this study, the structural, elastic, electronic, vibrational and thermal properties of the CsCl-type crystal structure of the ErAu binary alloy with two atoms in the unit cell are investigated in the framework of the first principles approach. The lattice parameter is found as 3.603 Å. Obtained structural parameters are consistent with the available studies. Considering of electronic properties, the electronic band structures, total and partial density of states of the ErAu alloy are determined. From these calculations, it has been decided that ErAu alloy is metallic in nature. The elastic constants are calculated using the stress-strain method. The elastic constants are also obtained for different pressure values. Elastic properties of the system present that ErAu alloy is mechanically stable at different pressure values. Phonon frequencies are calculated and the structure is determined as dynamically stable. To present the thermal properties of ErAu alloy, the free energy, entropy and heat capacity of the system are also obtained under increasing temperature values

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