Synthesis and Structure of LaSc2N@C-s(hept)-C-80 with One Heptagon and Thirteen Pentagons

摘要

The synthesis and single-crystal X-ray structural characterization of the first endohedral metallofullerene to contain a heptagon in the carbon cage are reported. The carbon framework surrounding the planar LaSc2N unit in LaSc2N@C-s(hept)-C-80 consists of one heptagon, 13 pentagons, and 28 hexagons. This cage is related to the most abundant I-h-C-80 isomer by one Stone-Wales-like, heptagon/pentagon to hexagon/hexagon realignment. DFT computations predict that LaSc2N@C-s(hept)-C-80 is more stable than LaSc2N@D-5h-C-80, and suggests that the low yield of the heptagon-containing endohedral fullerene may be caused by kinetic factors.