Basınç altında α -PbO2 fazındaki SnO2’nin yapısal ve mekanik özelliklerinin araştırılması.

SnO2 has various specific and unique properties, which make this material very useful for many applications. The elastic constants of materials are very important because they are closely associated with the mechanical, physical and chemical properties. The structural and elastic constants of SnO2 were investigated using density functional theory (DFT) as implemented in VASP software. The lattice parameters, atomic positions and elastic constants were studied up to pressure of 18 GPa. The calculated elastic constants indicate that SnO2 is mechanically stable. Some fundamental physical quantities such as bulk modulus, Debye temperature, Poisson’s ratio, Young's modulus, shear modulus, and crystal anisotropy were derived calculated data. The phase transition from CaCl2 - type to α-PbO2 structure is obtained at 12.13 GPa. The Debye temperature of SnO2 was computed from the elastic moduli and sound velocities. The computed average linear compressibility of α-PbO2 structure is 1.90 TPa-1 in the x, y and z direction at ambient pressure. Also, the pressure-induced lattice (elastic) constants were fitted to the regression equation in order to make direct comparison to results obtained by other calculations. The results were compared with available theoretical and experimental data. [ABSTRACT FROM AUTHOR]