Ab initio study of electronic structure, bonding and optical properties of ternary A2B2In (A = Ca, Eu and B = Pd, Pt) indides

Abstract

Crystal structure, optical and electronic properties of metal rich intermetallic Ca2Pd2In, Ca2Pt2In, Eu2Pd2In and Eu2Pt2In compounds have been explored using density functional theory based orthogonalized linear combination of atomic orbitals (OLCAO) method and code. The local density approximation scheme has been employed to probe all the properties. The outcomes of the electronic structure revealed the conducting nature of ternary indides. Density of states plots of ternary indides exhibited an increased number of energy states moving from Ca2Pd2In, Ca2Pt2In, Eu2Pd2In to Eu2Pt2In at Fermi level which substantiate the metallic nature of these compounds. The localization index calculations reflected the highly delocalized states in the vicinity of Fermi level. The cationic behavior of Ca- and Eu-atoms and anionic character of Pd-, Pt-, In-atoms has been evaluated through the effective charge (Qα*) calculations. Bond order calculations indicated highest strength of Ca2Pt2In among the studied indides. Optical features in the form of complex dielectric function, optical conductivity and electron energy loss function have been thoroughly discoursed. Two eminent peaks in electron energy loss L(ω) spectra have been observed at 29.77 and 27.83 eV which are associated to the plasmonic resonance.