Liberation of three dihydrogens from two ethene molecules as mediated by the tantalum nitride anion cluster Ta₃N₂^- at room temperature

The reactivity of gas-phase cluster anions Ta₃N₂^- with C₂H₄ under thermal collision conditions was studied by mass spectrometry in conjunction with density functional theory calculations. The full dehydrogenation of the C₂H₄ molecule was observed, with the formation of two dihydrogen molecules. Interestingly, the two carbon atoms originating from the first C₂H₄ molecule are used to construct another cluster Ta₃N₂C₂^-, which can activate one more C₂H₄ releasing one H₂ molecule. Therefore, three dihydrogen molecules are liberated from two ethene molecules in the overall reaction. The full dehydrogenation of C₂H₄ by gas-phase anions as well as the structure and reactivity of M-N-C (M: transition metal) cluster is reported for the first time. The properties of Ta₃N₂^- and Ta₃N₂C₂^- elucidated herein are of use in providing fundamental information that is necessary to tailor the design of new and effective catalysts by applying the related materials.