Excited states analysis of sulfur substitutional impurities on (ZnO)6 clusters using DFT and TD-DFT

The geometric parameters characterization and ground state energies of (ZnO)6 nanoclusters were calculated using Density Functional Theory (DFT) with B3LYP and LanL2DZ basis set. Excited state energies, as well as absorption wavelength, were computed using Time Dependent-Density Functional Theory (TD-DFT) for both nanostructures in its pristine form and also for variants of these nanoclusters with sulfur applied as substitutional impurity at different locations within the structure. For the emission wavelength, the excited state geometry optimization was carried out with Hartree-Fock Configuration Interaction Singles (HF/CIS). Our theoretical results are new data related to the geometry as well as to the spectral absorption/emission properties of these novel nanostructures. These cluster variants present characteristics interesting for solar cells and optical applications that will be useful for future theoretical/experimental developments.