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Reaction of Ta₃ ^- Clusters with Molecular Nitrogen: A Mechanism Investigation.

ABSTRACT: Because of the inertness of molecular nitrogen, its practicable activation under mild conditions is a fundamental challenge. Ta₃ ^- is an exceptionally small cluster that reacts with N₂ at room temperature, leading finally to Ta₃N₂ ^-; Ta₃N₂ ^- also could react with N₂ at room temperature, leading finally to Ta₃N₄ ^-, a product of interest in its own right because of its potential as a nitrogen fixation medium. The mechanisms of the Ta₃ ^-- and Ta₃N₂ ^--mediated activation of the N≡N triple bond have been investigated. Our extensive computations elucidate mechanisms for the ready reactions, leading to stepwise cleavage of the N≡N bond. Initial isomeric N₂/Ta₃ ^- complexes, N≡N elongation, undergo a N≡N split over generally low barriers in a highly exothermic process. The nitrogen-atom or molecular exchange reactions found in the Ta₃N₂ ^-/N₂ system may be of paramount importance in both applied and fundamental studies.

SUBMITTER: Sun X

PROVIDER: S-EPMC9260930 | biostudies-literature |

REPOSITORIES: biostudies-literature

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