Protected but Accessible: Oxygen Activation by a Calixarene-Stabilized Undecagold Cluster

DFT computations show that calixarenes stabilize subnanometer Au-11 clusters allowing access of small molecules like O-2 to reactive metal sites in the core. Maximum of three dioxygen molecules can bind to the cluster, and they are activated to a superoxo O-2(-) state. This study predicts that gold clusters could act as viable oxidation catalysts at ambient conditions based on similar principles as the metal centers in enzymes.