AB-INITIO CALCULATIONS OF STRUCTURAL, ELECTRONIC AND MAGNETIC PROPERTIES OF LiRh2Si2

Abstract

Abstract In this study, we investigated the structural, electronic and magnetic properties of the tetragonal LiRh₂Si₂ using the full-potential linearized augmented plane wave (FP-LAPW). The structural calculations were performed with four exchange and correlation potential (GGA- PBE, LDA-PW, GGA-WC and GGA-PBEsol), the electronic and magnetic properties were performed with GGA-PBE implemented in Wien2k code. We have obtained the cell dimensions, bulk modulus, and its pressure derivative.  The calculated lattice parameters are in good agreement with experimental and previous theoretical results. We calculated cohesive energy as 4,95 eV/atom and LiRh2Si₂ has good stability. Electron density plot of LiRh₂Si₂ shows strong covalent interactions between Si-Si and Rh-Si elements. We performed spin polarize calculation of Density of States (DOS).  Electronic band chart that show LiRh₂Si₂ has metallic feature for both spin up and spin down configurations. The spin up and spin down electronic band chart nearly symmetric so the compounds has nonmagnetic feature. We searched pressure effect on magnetic moment of LiRh₂Si₂. The magnetic moment of   LiRh₂Si₂ has been found 0.00075 ()  and it  decreased with increase of pressure. 

Keywords

• LiRh2Si2,Ab-intio calculations,Wien2k,FPLAPW,structural properties,magnetic properties

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