Abstract
The interaction between a xenon atom and aromatic π electron system is generally of van der Waals force with a specifically weak strength. In this work, we suggest the introduction of Cu ion will highly affect the binding behaviour between the xenon and π systems. Once Cu2+ ion locates above the benzene ring, the binding is surprisingly strengthened to 11.98 kcal mol−1 at CCSD(T)/CBS level, which is significantly stronger than average strength of the H-bonds in Watson-Crick guanine-cytosine base pair. If the Cu2+ is reduced to Cu+, the interaction of interest returns to the weak van der Waals interaction again. This phenomenon indicates the oxidation state shift of Cu ion could regulate the binding strength of Xe with π systems, which would be important for their potential biological functions. This study may provide a plausible understanding of the recent experimental observations of xenon anaesthesia.