Investigating the adsorption of H2O on ZnO nanoclusters by first principle calculations

► H2O either adsorbs or dissociates on ZnO nanoclusters. ► This depends on the stability of the clusters and the direction of approach. ► The band gap and excitation energies do not change significantly as a result of H2O adsorption. ► New IR frequency bands appear in the spectrum due to H2O adsorption.