On the Role of the Electronic Structure of the Heteronuclear Oxide Cluster [Ga2Mg2O5](center dot+) in the Thermal Activation of Methane and Ethane: An Unusual Doping Effect

摘要

The reactivity of the heteronuclear oxide cluster [Ga2Mg2O5](center dot+), bearing an unpaired electron at a bridging oxygen atom (O-b(center dot-)), towards methane and ethane has been studied using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Hydrogen-atom transfer (HAT) from both methane and ethane to the cluster ion is identified experimentally. The reaction mechanisms of these reactions are elucidated by state-of-the-art quantum chemical calculations. The roles of spin density and charge distributions in HAT processes, as revealed by theory, not only deepen our mechanistic understanding of C-H bond activation but also provide important guidance for the rational design of catalysts by pointing to the particular role of doping effects.