A DFT study to investigate structural, electronic, optical, mechanical and magnetic properties of NaGeBr3 for photovoltaic and optoelectronic applications

The first-principles calculations have been used to investigate the structural, electronics, optical, mechanical, and magnetic properties of NaGeBr₃ with the help of Cambridge Serial Total Energy Package (CASTEP) code. The DFT + U approximation is used for all calculations to obtain the better results. The calculated value of tolerance factor is 0.88 which confirms the cubic phase of NaGeBr₃. The electronic properties show that the material has a direct band gap nature with a value of 2.90 eV. The mechanical stability of the material is confirmed by the Born stability criteria. The Pugh’s ratio and Poisson’s ratio show that the material is ductile in nature. The optical properties show that the material has high absorption and conductivity. The magnetic properties show that the material is antiferromagnetic in nature. Due to the direct band gap nature, the material can be utilized in photovoltaic and optoelectronic devices. In addition, the thermoelectric properties of the material also have been analyzed, and the results imply that it has the potential to be exploited for thermoelectric devices.