Abstract
We performed extensive density functional calculations on various metallofullerene complexes and their polyanions to gain insight into novel η1 and η2[6:5] motal (M)-C60 bonding modes. For LnMC60 (L =ligand), the η1 mode is calculated to be the most stable, followed by η2[6:5] and η2[6:6] for -3 anions, in contrast to η2[6:6] >> η2[6:5]= η1 for neutral cases. This observation is responsible for the transformation from η2[6:6] to η1 for LnM3C60, such as [OS3(CO)9C60], upon successive electron reductions. Our onergy partitioning analysis (EPA) indicates that the π-type character of η2[6:6] is much larger than that of η2[6:5], An electron addition decreases the π-type interaction of both the η2[6:6] and η2[6:5] modes by about 35%, whereas it has little effect on σ-type interactions. Because of the large proportion of π-character in η2[6:6] coordination, the stability of η2[6:6] coordination decreases steeply as electron reductions continue. On the basis of the EPA results, we could explain why the reaction of [Os3(CO)8(CNR)(μ3η 2[6:6], η2[6:6]-C60)] (R = CH 2Ph) With CNR (4e donor) produces [Os3(CO) 8(CNR)(μ3-CNR)(μ3-η1- C60)]. The η1 and η2[6:5] bonding modes of M-C60 are crucial to fully understand the bonding nature of M-C60 bonds in exohedral metall of ullerene complexes.
Original language | English |
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Pages (from-to) | 1530-1535 |
Number of pages | 6 |
Journal | European Journal of Inorganic Chemistry |
Issue number | 10 |
DOIs | |
State | Published - 2010 |
Keywords
- Bonding modes
- Cluster compounds
- Density functional calculations
- Fullerenes
- Transition metals