The cage and metal effect: spectroscopy and electrochemical survey of a series of Sm-containing high metallofullerenes.
A series of Sm-containing high metallofullerenes, namely, Sm@C82 (I, II, III, IV), Sm@C84 (I, II, III), Sm@C86, Sm@C88 (I, II, III), Sm@C90 (I, II, III), Sm@C92 (I, II), Sm@C94 (I, II, III), and Sm@C96, is successfully synthesized and characterized by UV/Vis/NIR absorption spectroscopy, and cyclic and differential pulse voltammetry. Sm-containing high metallofullerenes have a relatively larger number of isomers compared with other divalent ones. The highest boiling point of Sm among Group II metals may be responsible for this phenomenon. Comparing the spectroscopic and electrochemical behaviors of Sm-containing metallofullerenes with those of other divalent ones, it is seen that when the size of the carbon cage enlarges, different structures form stable molecules with different metals. Furthermore, there are also some important differences in the electrochemistry properties. The cage effect on the electronic structures of high metallofullerenes is also estimated from the differences in reduction potentials between metallofullerenes and their corresponding fullerenes. It is believed that the influence of transferred electrons from the metal to the carbon cage becomes much weaker for high fullerenes. The redox property of high metallofullerene is more dependent on the carbon-cage structure than the effect of electron transfer.
Liu
Jia
J
Beijing National Laboratory for Molecular Science, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China.
Shi
Zujin
Z
Gu
Zhennan
Z
D055664:Electrochemical Techniques; D037741:Fullerenes / Q000737:chemistry*; D010084:Oxidation-Reduction; D012493:Samarium / Q000737:chemistry*; D013057:Spectrum Analysis
D037741:Fullerenes; D012493:Samarium