First principles study of structural, elastic and electronic properties of ACY3 (A = Al, In and Tl)

Structural, elastic and electronic properties of ACY3 (A = Al, In and Tl) were investigated by means of pseudopotential plane wave method (PP–PW). Our calculated lattice parameters and equilibrium volumes are in good agreement with the available experimental data. Predicted single crystal elastic constants show a weak dependence on the substitution of Al by In or Tl atoms. Also polycrystalline elastic moduli (B, G, E, v and A) were deduced and compared to those of related antiperovskite compounds. From the B/G ratio, we have observed that these compounds can be classified as brittle materials. The band structure shows a metallic character, the conductivity is mostly governed by the Y d states. Hybridization states along Y–C atoms and Y–A atoms show respectively a mixture of ionic-covalent and pure ionic bonding in the charge density maps.