Pressure effect on the structural, electronic, optical and elastic properties of Zn0.75Be0.25O from first-principles calculations

In this work we focused on the effect of the pressure on the material because of its great importance in different environments. A first principles study has been performed to calculate the structural, electronic, optical and elastic properties of Zn0.75Be0.25O under different pressures. Our results of the transitions from wurtzite (B4) to rocksalt (B1) structure occur around 11.04 GPa and 13 GPa for ZnO and Zn0.75Be0.25O, respectively. The lattice constants decrease and the band gap increases with increasing pressure. The valence band maximum moves to lower energy, whereas the conduction band minimum moves to higher energy with increasing pressure, so the band gap broadens. The curve shape for optical parameters is almost unchanged within creasing pressure, but all the peaks moves to higher energy (blueshift). Our results provide a theoretical reference for the design of UV devices comprising Be-doped ZnO. Finally, our results are predictions at different pressures.