On the Origin of the Remarkably Variable Reactivities of [AlCeO x]+ ( x=2 -4) towards Methane as a Function of Oxygen Content.

The thermal gas-phase reactions of the closed-shell heteronuclear metal-oxide clusters [AlCeOx]+ ( x=2-4) with methane have been explored by FT-ICR mass spectrometry and high-level quantum-chemical calculation. Whereas [AlCeO2]+ and [AlCeO4]+ are inert towards methane under ambient conditions, [AlCeO3]+ spontaneously abstracts one hydrogen atom from methane. Mechanistic aspects have been addressed to reveal the reasons for the rather distinct reactivities of the [AlCeOx]+/CH4 couples, and the electronic origins of the unprecedented single hydrogen-atom abstraction from methane by closed-shell [AlCeO3]+ are discussed. [ABSTRACT FROM AUTHOR]