Methane Activation by Iron-Carbide Cluster Anions FeC6(-).
Laser-ablation-generated and mass-selected iron-carbide cluster anions FeC6(-) were reacted with CH4 in a linear ion trap reactor under thermal collision conditions. The reactions were characterized by mass spectrometry and density functional theory calculations. Adsorption product of FeC6CH4(-) was observed in the experiments. The identified large kinetic isotope effect suggests that CH4 can be activated by FeC6(-) anions with a dissociative adsorption manner, which is further supported by the reaction mechanism calculations. The large dipole moment of FeC6(-) (19.21 D) can induce a polarization of CH4 and can facilitate the cleavage of C-H bond. This study reports the CH4 activation by transition-metal carbide anions, which provides insights into mechanistic understanding of iron-carbon centers that are important for condensed-phase catalysis.
†Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Hai-Fang
HF
Li
†Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Zi-Yu
ZY
Li
†Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.|‡University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Qing-Yu
QY
Liu
†Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Xiao-Na
XN
Li
†Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Yan-Xia
YX
Zhao
†Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Sheng-Gui
SG
He
density functional calculations; dipole moment; iron-carbide clusters; mass spectrometry; methane activation