Electronic Band Structure, Bonding, and Optical Properties of Yb 2 Cd 2 Pn 3 (Pn = P, As, Sb, Bi) Compounds: A DFT Investigation

ABSTRACT The physical characteristics of four Zintl compounds Yb 2 Cd 2 Pn 3 (Pn = P, As, Sb, Bi) have been thoroughly examined using first‐principles calculations. The density functional theory based Vienna ab initio simulation package has been employed. These Zintl phases demonstrate a monoclinic crystal arrangement characterized with space group C2/m (No. 12). The computed band gap values using GGA (meta‐GGA) 0.5327 (0.8302), 0.3061 (0.5934), and 0.2891 (0.3597) eV indicate the semiconducting nature of all studied compounds except Yb 2 Cd 2 Bi 3 which exhibits semimetallic nature, with valence band dominated by p‐orbital of pnictogen atom and conduction band by Yb‐d states. The effect of SOC has been further investigated to account for relativistic effects, yielding band gap values of 0.5266, 0.2927, and 0.1345 eV for Yb 2 Cd 2 P 3 , Yb 2 Cd 2 As 3 , and Yb 2 Cd 2 Sb 3 , respectively. The –COHP spectra reveal that the Pn–Cd atomic pair plays an appreciable role in stabilizing the crystalline structures. The optical parameters have been analyzed upon incident radiation along the X , Y , and Z directions. The titled compounds exhibit strong absorption in the ultraviolet and unique plasmonic attributes, emphasizing their potential for use in plasmonic and optoelectronic applications. Moreover, the reflectivity and energy‐loss spectra suggest that Yb 2 Cd 2 Pn 3 compounds hold strong potential for use in optical coatings and advanced photonic devices. Further, the bonding characteristics of all Zintl phases have been observed from charge transfer analysis.