Ab Initio Study of the Electronic, Thermodynamic, Thermoelectric, and Optical Properties of HfSeS in the (100), (110), and (111) Crystallographic Directions

In this article, the results of theoretical calculations are presented on the structural, electronic, thermodynamic, thermoelectric, and optical properties of the compound HfSeS grown in the (100), (110), and (111) crystallographic directions. These properties are studied with the aid of calculations based on density functional theory, using the Generalized Gradient Approximation (GGA) approximation and spin‐orbit coupling (SOC). These electronic calculations reveal that HfSeS exhibits an indirect band gap of the M‐Γ type for all directions, with strong alignment between the results obtained employing the GGA and SOC approaches. For the study of optical properties, pressure is applied to better understand the properties of the material under various conditions. The thermodynamic properties of HfSeS are calculated, including heat capacities, thermal expansion, Debye temperature, and entropy, under elevated pressures and temperatures. These calculations are performed using the quasi‐harmonic Debye model integrated into the Gibbs2 code, and the results are analyzed in detail to better understand the thermodynamic properties of the material under various conditions. Finally, the thermoelectric properties such as the Seebeck coefficient and the electronic thermal conductivity are analyzed.