A comprehensive study on the structural, electronic and nonlinear optical (NLO) properties of alumina nanostructures (Al2O3)n with n = 2-5 belonging to the groups III and VI dopants carried out by density functional theory. The NBO charges exhibit dopant atoms caused to the increasing charge transfer and introduces acceptor-donor model for NLO response of alumina nanostructures. Under the influence of doping S and Se, the energy gap decreases, because high energy level is formed as the new HOMO orbitals in the primary gap of pristine nanostructures. Furthermore, the results of the present study show that dopant atoms enhance NLO response in the alumina nanostructures and the greatest values are obtained for and γtot through doping Se in Al10O15.
