First-principles study of the electronic structure, optical, thermodynamic, and thermoelectric nature in MgACu₃Se₄ (A = Sc, Y) semiconductors

Semiconductors with direct band gaps are outstanding for their use in most optoelectronic devices specifically for solar cells. Here we studied the optoelectronic, thermodynamic, and thermoelectric features of novel MgACu₃Se₄ (A = Sc, Y) semiconductors. Cutting-edge computations that employs density functional theory is used. The predicted density of state plots validated the electronic band structure results. A direct type of energy gap with a semiconducting behavior was noticed from the electronic band profiles of both materials. The significant optical response for the incident photon energy range of 0–14 eV is also revealed and discussed in detail. By using the quasi-harmonic Debye model, we additionally examined the thermodynamic characteristics of these quaternary systems and analyzed how their cell volume, Debye temperature, heat capacity, thermal expansion coefficient, and Grüneisen constant change over the pressure and temperature range from 0 up to 20 GPa and 0 up to 1200 K, respectively. Furthermore, the important thermoelectric transport parameters were evaluated and discussed for their thermoelectric application.