Investigation of the structural, electronic, elastic, dynamic and thermodynamic properties of the NiAs2 crystal by density functional theory

In this thesis, some physical properties of 〖NiAs〗_2 crystal, which is in simple cubitic structure, were investigated by using ABINIT computer program based on density functional theory under generalized gradient approach (GGA) and local density approach (LDA). For this, first the cut-off energy value and the number of k points for the 〖NiAs〗_2 crystal were obtained. Then, structural optimization was done by using these data and the theoretical values of the lattice parameters were found. By using these values, the electronic properties of the 〖NiAs〗_2 crystal were investigated and it was observed that this crystal had no forbidden band gap and it shows metallic property. Then, elastic properties were examined by calculating the properties such as Bulk module, Young's modulus, Shear module, Debye temperature, elasticity properties. Finally, the dynamic and thermodynamic properties were examined and computed and all the results were given with tables and graphs. Since there is not much study in the literature related to this crystal, few of the results have been compared with the literature. However, it is seen that the values we obtained are in great aggrement with the literature as a result of the comparison with the literature.