B2 fazda intermetalik RuTi alaşımının elektronik, elastik ve fonon özelliklerinin incelenmesi

The basis of density function theory (DFT) is the work done by Thomas and Fermi in 1927.Density function theory (DFT), which can calculate electronic structures of atoms, molecules and solids; Is a successful theory that is widely used both in solid-state physics and material science and is compatible with experimental results. This success of the density function theory is based on the fact that the methods are based on the first principles and aims to explain the properties of the materials by taking advantage of the basic quantum mechanics laws. One of the basic quantities used to describe the electronic state of a material is the electronic state density (DOS). The state density for electrons in an energy band gives the number of states that can be occupied by electrons at a given energy interval. Elasticity defines the elastic constant which is the measure of the response of the crystal to an external force applied and plays a very important role when it is desired to investigate the rigidity, mechanical stability of the material, and the bond strengths between the nearest neighbor atoms of the constituent atoms. The Volume Module(B) is an important feature that represents the theoretical and experimental rigidity of a material (especially cubic crystals). It is defined as a measure of the energy required to resist a change in the volume of a material by compression of a material under hydrostatic pressure, or to produce a deformation. The Shear Module(G) is the most important parameter that determines the hardness of a material and is a measure of resistance of a material to its surface against the strain of another material. In this work, structural, elastic, electronic, thermodynamic and phonon properties of RuTi alloy in B2 (CsCl) phase were investigated by employing first-principles calculations in the generalized gradient approach. The lattice constant, the static bulk modulus, the pressure derivative and the elastic constants of the bulk modulus of the RuTi alloy were found. The brittleness and ductility properties of the RuTi alloy at the B2 phase were evaluated by the Poisson sigma ratio criterion and the Pugh criterion. The B / G value of the RuTi alloy in the B2 structure is 1.977. According to these criteria, it can be said that the RuTi alloy is a ductile material. The electronic structure of the RuTi alloy and the phonon frequency curves were gathered. The position of Fermi level of these systems was calculated and discussed. The electronic band structure, total electronic and partial state densities of the RuTi alloy were calculated and analyzed based on the comparison of the current available data. The density of states around the Fermi energy (EF) has been argued elaborately by examining the contribution of the d-electrons. It was determined from the density of the state and band structure that this alloy showed metallic character in the B2 phase. Phonon distribution curves and their corresponding total and predicted intensities are calculated for the first time in the context of density functional perturbation theory. In this work, Phonon density states and quasi-harmonic approximations were used to estimate and some thermodynamic properties, such as the specific heat capacity of the RuTi alloy in the B2 phase at constant volume. A linear-response approach was used to calculate the full phonon spectrum and state density. he specific heat capacity (Cv) for the RuTi alloy in the fixed volume was calculated.