Due to their direct energy bandgaps and other unique structural, electrical, and optical properties, II-VI binary semiconductors have piqued the interest of many technological applications, including spintronics, optoelectronics, solar cells, photovoltaic cells, photodetectors, light-emitting diodes, and so on. [1][2][3][4][5][6][7] For example, ZnSe and its alloys are appealing materials for lightemitting diodes and laser diodes. These days, mercury-cadmium telluride is widely used in infrared detector arrays. Because of their nonlinear properties, CdS, CdSe, and CdTe, as well as their alloys, have sparked intense interest for their use in photovoltaic devices and other optoelectronics applications. [8][9][10][11][12][13] Depending on the synthesis conditions, CdX (X = S, Se, and Te) semiconductors can crystallize into various structures, including wurtzite and zinc-blende. Theoretical investigations predicted that CdX (S, Se, and Te) semiconductors are stable in both the zinc-blende and wurtzite phases, whereas experimental studies revealed that for CdS and CdSe, the wurtzite phase is stable, and CdTe is stable in the zinc-blende structure. [14][15][16][17][18][19][20] The present study examines both the zinc-blende and wurtzite forms of CdX semiconductors.CdX (X = S, Se, and Te) semiconductors have been studied extensively for various potential applications. [21][22][23] Theoretically, numerous works based on ab initio approaches have examined the structural, electronic, elastic, and optical properties of these chalcogenides so far. Guo and co-workers have studied the electronic, mechanical, optical, and thermodynamical properties of CdS, CdSe, and CdTe in the cubic zinc-blende crystal structure. [24] Boutaiba and co-workers investigated the relativistic effects on the fundamental properties of binary semiconductors CdX (X = S, Se, and Te) such as structural, electronic, optical, and transport properties. [25] The electronic structures of the abovementioned binary semiconductors were examined by John et al. in both the wurtzite and zinc-blende forms. [26] The behavior of the electronic, elastic, and lattice dynamical properties of the CdX (X = S, Se, and Te) semiconductors under pressure was investigated by Deligoz et al. [27] Yamçiçier and co-workers studied the transition mechanism of the wurtzite phase of CdTe under high pressure and found that wurtzite CdTe undergoes a phase transition at high pressures of 10 and 140 GPa to zinc-blende and orthorhombic structures, respectively. [28] The stability, electronic, and optical properties of CdTe under hydrostatic pressure were examined by Liu and co-workers. [29] Recently, the electronic, optical, and thermoelectric properties of CdX (X = S, Se, and Te) monolayers were reported by Naseri et al. [30] Mohanta and co-workers investigated the elastic, piezoelectric, electron, and phonon transport properties of hexagonal buckled CdX (X = S, Se) monolayers using the first-principles method. They predicted ultralow lattice thermal conductivity of 1.08 and 0.75 W m À1 K...