Study of the fundamental physical characteristics of the Zintl phase K2BaCdSb2

• Published in: Computational Condensed Matter 2024-12, Vol.41, p.e00966, Article e00966
• Main Authors: Nasrallah, Hadjer, Guechi, Nacir, Bouhemadou, Abdelmadjid, Essaoud, Saber Saad, Bin-Omran, Saad
• Format: Article
• Language: English
• Subjects: Ab initio calculations; Elastic moduli; Electronic structure; Thermoelectric properties; Zintl phase
• ISSN: 2352-2143; 2352-2143
• DOI: 10.1016/j.cocom.2024.e00966

The structural, elastic, thermodynamic, electronic, and thermoelectric characteristics of K2BaCdSb2 were investigated utilizing ab initio methods. The structural, elastic, and thermodynamic properties were calculated using the pseudopotential plane wave approach with the GGA-PBEsol exchange-correlation functional. The computed equilibrium structural characteristics closely match the available data. The anticipated elastic constants reveal that K2BaCdSb2 is mechanically stable, brittle, and exhibits significant elastic anisotropy. The full potential linearized augmented plane wave approach with the Tran-Blaha modified Becke-Johnson potential was used to determine the electronic structure of K2BaCdSb2.It is found that K2BaCdSb2 is a semiconductor with a Γ-Γ type direct bandgap of 0.85 eV. Bonding analysis shows the bond between Cd and Sb atoms within the [CdSb2]4− polyanion is of covalent nature and that between the K/Ba atom and the [CdSb2]4− polyanion is of ionic character. The thermoelectric characteristics of K2BaCdSb2 were analyzed at a temperature of 500 K for of charge-carrier concentrations from 1 × 1018 to 3 × 1020 cm−3.When the concentration of holes is 1.0 × 1020 cm−3, The power factor reaches a value of 17 × 1010 W m−1 K−2.s−1 for a hole concentration of 1.0 × 1020 cm−3. For the p-doped K2BaCdSb2 with a concentration of 1.0 × 1018cm−3, the electronic figure of merit is 0.95.