A quantum-chemical study of CO adsorption on small Cu particles supported on reduced SiO2

The adsorption of CO over Cu1, Cu2 and Cu3 deposited on a SiO defect of silica was studied using DFT. The CO adsorption strength follows this order: Cu1 > Cu2 ≥ Cu3. While for closed-shell systems CO shows the lower frequency shifts, for the open-shell systems the behaviour is the opposite. This could be related with the variation of polarizabilities when CO interacts with Cun/SiO2.