Electronic band profiles and optical response of Cd3Y2 (Y= N, P and As) compounds

Cubic and tetragonal phases of Cd3Y2 (Y= N, P and As) compounds are studied using full potential approach of density functional theory. All the studied crystal structures were fully optimized using the generalized gradient approximation. Calculated structural parameters agree well with experimental measurements. Electronic band profiles reveal metallic nature of Cd3Y2 in both phases except Cd3P2 which is semiconductor with small band gap value. The charge sharing is dominant in cubic and tetragonal phases which show covalent bond nature. Optical properties of the compounds are studied in detail in both phases. Interestingly, it is revealed that the intraband transitions play vital rule in explaining the optical properties in the metals while no influence observed in the Dirac semi-metal and semiconducting nature in these compounds. The reflectivity of metallic behavior compounds Cd3P2 and Cd3As2 reached up to 90% with the intra band calculation.