Mixed Dimetallic Cluster Fullerenes: ScGdO@C-3v(8)-C-82 and ScGdC2@C-2v(9)-C-82

摘要

Mixed-metal cluster fullerenes have been extensively studied in recent years for their rich structural variability of the encaged clusters and have shown great potential in applied studies such as biomedicine and molecular electronic devices. However, the studies in this field have mostly concentrated on the nitride cluster fullerene, and very few other types of mixed-metal cluster fullerenes have been reported so far. Herein, we report the synthesis and isolation of the first mixed-metal oxide cluster fullerene, ScGdO@C-82, and a novel mixed dimetallic carbide cluster fullerene, ScGdC2@C-82. Spectroscopic and electrochemical studies combined with density functional theory (DFT) calculations assigned the molecular structure of the two cluster fullerenes (CFs) to ScGdO@C-3v(8)-C-82 and ScGdC2@C-2v(9)-C-82, respectively. DFT calculations also suggested that these two mixed-metal clusters are likely to be found in any of the three isolated pentagon rule C-s(6)-C-82, C-3v(8)-C-82 and/or C-2v(9)-C-82 cages. The electrochemical studies show that the electrochemical gap of ScGdO@C-3v(8)-C-82 and ScGdC2@C-2v(9)-C-82 are 1.49 and 1.08 V. Moreover, comparative studies of ScGdO@C-3v(8)-C-82 and Sc-2@C-3v(8)-C-82, ScGdC2@C-2v(9)-C-82 and Sc2C2@C-2v(9)-C-82 showed that, despite their close structural resemblance, the replacement of one Sc ion by a Gd ion resulted in notable changes in their electrochemical behaviors as well as their Sc-45 NMR spectra.