Theoretical investigation of the structural properties of SnSe1-xSx: A density functional study

Pressure and doping tuning provide an important gateway to the discovery of materials with improved characteristics by modifying the interaction parameters and material structural characteristics and other properties. The enhancement of the thermoelectric properties of the multivalley systems like SnSe has emerged as a key aspect for new technologies. In order to understand the evolution of the characteristics, we study SnSe1-xSx, for x=0, 0.25, 0.5, 0.75 and 1. The elastic constants of SnSe1-xSx, were calculated to analyze the mechanical stability of the structures. Moreover, the Voigt-Reuss-Hill method was used to determine the elastic moduli. Furthermore, the evolution of SnSe1-xSx, under high pressure was also analyzed. The pressure induced semiconductor-metal phase transition was monitored. Dependencies of the energy-gap values on doping and pressure demonstrate a substantial increase with the increase in the S content. Band-structures, density of states and Fermi level shift corroborate the above characteristics. Pressure and doping dependencies of the Raman spectra have also been considered. Our comprehensive study on the effects of pressure and doping on this system should lead to tuning of the materials properties for advanced technological applications.