Optical and Electronic Properties of Al-Doped Mg12O12 Nanocluster: A Theoretical Study

Effects of A doping on the structural, optical, and electronic properties of Mg12O12 nanocluster have been investigated using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. It is found that for all stable structures, the doped nanocluster with five Al atoms has a larger binding energy of −5.22 and −5.06 eV evaluated by M06-2X and B97D functional, respectively. Both M06-2X and B97D functional exhibited that the Al substituted at the Mg-site can alter the energy gap of the nanocluster in comparison with unstable O sites. With substituting four Al atoms at the Mg sites of the nanocluster, the changes in the energy gap is significantly large than other states. More details on the dopant effects, charge population and electronic structure evolution with the variation of the Al concentration of doping are discussed in the context.