Ab initio studies of the structural, elastic, electronic and thermal properties of NiTi2 intermetallic

Abstract

First principles calculations were performed in the framework of the density functional theory (DFF) using the Full Potential-Linear Augment Plane Wave method (FP-LAPW) within the generalized gradient approximation (GGA) to predict the structural, electronic, elastic and thermal properties of NiTi2 intermetallic compound. By using the Wien2k all-electron code, calculations of the ground state and electronic properties such as lattice constants, bulk modulus, presure derivative of bulk modulus, total energies and density of states were also included. The elastic constants and mechanical properties such as Poissons ratio, Youngs modulus and shear modulus are estimated from the calculated elastic constants of the single crystal. Through the quasi-harmonic Debye model, the preasure and temperature dependences of the linear expansion coefficient, bulk modulus and heat capacity have been investigated. Finally, the Debye temperature has been estimated from the average sound velocity according to the predicted polycrystal bulk properties and from the single crystal elastic constants. (C) 2015 Elsevier Ltd. All rights reserved.