Activation of Methane by Oligomeric (Al₂O₃)x⁺ (x=3,4,5): The Role of Oxygen-Centered Radicals in Thermal Hydrogen-Atom Abstraction

A matter of radical sites and bond energies: Experimental and theoretical studies show that the cationic polynuclear aluminum oxide clusters, which are oligomeric systems of (Al2O3)x+ (x=3, 4, 5), activate methane at room temperature (see picture). In contrast, clusters with an odd number of aluminum atoms are unreactive.