The ınvestıgatıon of structural, electronıc and phonon propetıes of ırx (x=sc, al ve ga) compounds ın cscl (b2) phase usıng the densıty functıonal theory

In this thesis, the elastic, electronic, and phonon properties of the compounds IrX (X=Al, Sc and Ga) in the B2 (CsCl) structure have been investigated in detail by employing an ab initio pseudopotential method and a linear-response technique within a generalized gradient approximation (GGA) of the density functional theory (DFT) scheme. The ground state quantities such as lattice parameter, bulk modulus and first-order pressure derivative of the bulk modulus, were evaluated. The elastic constants are calculated from the phonon dispersion curves. The electronic band structures of IrX (X=Al, Sc and Ga) show that at the Fermi level, a major part of the contribution comes from Ir 5d states. The phonon-dispersion curves and phonon total and partial density of states based on the linear-response method have been investigated for all materials.