Electronic and optical properties of cubic bulk and ultrathin surface [001] slab of CsPbBr3

First Principles calculations were performed on the cubic bulk and its (001) surface of CsPbBr 3 to reveal its elastic, electronic and optoelectronic properties. The cubic bulk phase is investigated for its mechanical stability and bypasses its other structural phases. Various calculation schemes like GGA, GGA+SOC and the highly recommended modified Becke Johnson (mBJ) potential are applied. The electronic energy bandgap obtained from GGA, GGA+SOC and mBJ are found to be ∼ 1.89 eV, ∼ 1.52 eV and ∼ 2.25 eV, respectively for the bulk system. The result of mBJ is in close approximity with the available experimental results. The high optical spectra of absorption coefficient ( α × 10 7 /cm) is observed in the energy range of 3–6 eV for both the bulk and the surface. These values of absorption coefficient surpass non-lead based cubic halides and zinc based organic-inorganic hybrids.