First Principles Study on Structural and Electronic Properties of REAg (RE= Y, La, Pr and Er) Intermetallics

We The structural, electronic and mechanical properties of binary B2 – type CsCl structured intermetallic compounds of Ag (ReAg, Re= Y, La, Pr and Er) have been studies systematically by means of first principles density functional theory within generalized gradient approximation. Ground state properties such as lattice constant (a0), bulk modulus (B) and its pressure derivative (B?) are obtained. The present results are in good agreement with the experimental and other theoretical calculation available. Amongst all the Intermetallics is found ErAg to be most ductile due to the presence of strong metallic bonding. Keywords: Intermetallic compounds; Density Functional Theory; Ductility; Electronic Structure

A First Principle Study of Pressure Induced Structural and Electronic Properties in Neptunium Bismuthide

We have examined the pressure induced structural and electronic   properties of neptunium monobismuthides. The total energy as a function of volume is obtained by means of self-consistent tight binding linear muffin-tin-orbital (TB-LMTO) method within the local density approximation (LDA). It is found that NpBi is stable in NaCl – type structure under ambient pressure. We predict a structural phase transition from NaCl-type (B1-phase) sructure to CsCl-type (B2-phase) structure for NpBi in the pressure range of 11 GPa. We also calculate the lattice parameter (a0), bulk modulus (B0), band structure and density of states. From energy band diagram it is observed that NpBi exhibit metallic behaviour. The calculated equilibrium lattice parameters and bulk modulus are in general good agreement with available experimental data. Keywords: Structural phase transition; Electronic band structure; Metallic