13C and 139La NMR Studies of La2@C80: First Evidence for Circular Motion of Metal Atoms in Endohedral Dimetallofullerenes


  • This work was partly supported by a grant from the Uchida Energy Science Promotion Foundation and a Grant-in-Aid for Scientific Research on Priority Areas (No. 09238211) from the Ministry of Education. Science, Sports, and Culture, Japan.


original image

Clear confirmation of recent theoretical studies concerning the structure of the endohedral complexes formed by La and C80 is provided by the NMR spectroscopic investigations presented here Complex La2@C80 is present, and its structure is based on the unstable “empty” Ih isomer of C80. The two La atoms circulate inside this round cage even at room temperature (shown schematically on the right).