Extensive DFT calculations are performed to optimize the geometric structures of O-rich tungsten oxide clusters, to simulate the PES spectra, and to analyze the chemical bonding. The ground-state structure of W4O14-is best considered as W4O12(O2-), containing a side-on bound superoxide ligand. The current study indicates that the extra electron in W4O12-is capable of activating dioxygen by non-dissociative electron transfer (W 5d → O2 π*), and the anionic clusters can be viewed as models for reduced defect sites on tungsten oxide surfaces for the chemisorption of O2.
The electronic and structural properties of ReO5 and ReO5 clusters are investigated using density functional theory (DFT) calculations. The lowest energy structures for both the anionic and neutral clusters are determined, and the corresponding photoelectron spectrum is simulated. Our results show that ReO5 can be described as an unusual peroxo molecule, Re(O)3(η2-O2) , while ReO5 is found to be exhibiting the O2 o radical character. Molecular orbital analyses and spin density analyses are performed to elucidate the chemical bonding and the electronic and structural properties in these two rhenium oxide clusters.
