The influence of Sc doping on structural, electronic and optical properties of Be12O12, Mg12O12 and Ca12O12 nanocages: a DFT study.

Density functional theory (DFT) calculations were used to study the effect of scandium doping on the structural, energetic, electronic, linear and nonlinear optical (NLO) properties of Be12O12, Mg12O12 and Ca12O12 nanoclusters. Scandium (Sc) doping on nanoclusters leads to narrowing of their E g, which enhances their conductance greatly. Also, the polarizability (α) and first hyperpolarizability (β0) of nanoclusters were dramatically increased as Be, Mg or Ca atoms are substituted with a Sc atom. Among all clusters, α and β0 values for Sc-doped Ca12O12 were the largest. Consequently, the effect of the doping atom, as well as of cluster size, on electronic and optical properties was explored. Time dependent (TD)-DFT calculations were also carried out to confirm the β0 values; the results show that the higher value of first hyperpolarizability belongs to Sc-doped Ca12O12, which has the smallest transition energy (ΔEgn). The results obtained show that these clusters can be candidates for using in electronic devices and NLO materials in industry.