Muhammet KARATAŞLI, Süleyman ÇABUK, Tahsin ÖZER

CaCl2 Fazda SnO2 Kristalinin Mekanik Özelliklerinin Araştırılması

Mekanik özellikler malzeme bilimi ve teknolojisinde kilit rol oynamaktadır. Mekanik özellikler, değişik basınç altında yoğunluk fonksiyonel teorisine dayanan ab-initio yöntemi ile genelleştirilmiş gradyent yaklaşımı (GGA) kullanılarak hesaplanmıştır.CaCl2 fazındaki SnO2'nin yapısal parametreleri belirlendi. Bağımsız elastik kat sayıları ve bulk modülü, Debye sıcaklığı gibi ilgili polikristal nicelikler Voight -ReussHill yaklaşımları kullanılarak hesaplandı. Ortam basıncında Debye sıcaklığı ve x, y ve z yönlerinde ortalama lineer sıkıştırılabilirlik sırasıyla 487,1K ve 1,89 TPa-1 olarak bulundu. Ayrıca, farklı basınçlarda örgü parametreleri ve elastik sabitler üzerinde regresyon analizi yapıldı ve basınca bağlı olarak regresyon eşitlikleri önerildi. Elde edilen sonuçlar önceki hesaplamalar ve mevcut deneysel verilerle karşılaştırılmıştır.

Investigation of Mechanical Properties of SnO2 Crystals in CaCl2 Type Structure

Mechanical properties play a key role in materials science and technology. The mechanical properties have been computed using the generalized gradient approximation (GGA) with ab-initio method based on density functional theory (DFT) under various pressures. Structural parameters of SnO2 in CaCl2type phase were determined. Independent elastic coefficients and related polycrystalline quantities such as bulk modulus, Debye temperature were calculated using the Voight -Reuss - Hill approximation. The Debye temperature and average linear compressibility in the x, y and z direction at ambient pressure were found to be 487.1 K and 1.89 TPa-1 , respectively. In addition, regression analysis was performed on the lattice parameters and elastic constants at different pressures and the regression equations were suggested depending on the pressure. The obtained results are compared with the previous calculations and available experimental data.

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