Isolation of a Small Carbon Nanotube: The Surprising Appearance of D_5h(1)‐C₉₀

Abstract

Vollkommen röhrenförmig: Das bislang nicht nachgewiesene höhere Fulleren D5h(1)‐C90 (siehe Struktur) wurde als Haupt‐C90‐Isomer isoliert, wenn von Sm2O3‐dotierten Graphitstäbchen ausgegangen wurde, und durch eine Röntgenstrukturanalyse charakterisiert.

Isolation of Four Isomers of C96 and Crystallographic Characterization of Nanotubular D3d(3)‐C96 and the Somewhat Flat‐Sided Sphere C2(181)‐C96

“…Interestingly, nanotubular fullerenes (i. e. D 5h (1)-C 90 , [13] D 3d (3)-C 96 , La 2 @D 5 A C H T U N G T R E N N U N G (450)-C 100 , [14] and Sm 2 @D 3d A C H T U N G T R E N N U N G (822)-C 104 . [15] ) occur for each of the largest cages that have been fully structurally characterized.…”

“…[16,17] Experimentally, Kikuchi, Achiba and co-workers briefly reported that they had isolated ten isomers of C 96 and identified their symmetries through 13 C NMR spectroscopy as C 1 (4 isomers), C 2 (3 isomers), C s (l isomer), D 2 (1 isomer), and D 3d (l isomer). [18] Kemnitz and Troyanov reacted C 2 F 5 I with a mixture of higher fullerenes and were able to obtain crystals of the adduct C 96 A C H T U N G T R E N N U N G (C 2 F 5 ) 12 , which were shown by singlecrystal X-ray diffraction to utilize the C 1 A C H T U N G T R E N N U N G (145)-C 96 cage.…”

“…To date, three isomers of C 90 (D 5h (1)-C 90 , C 1 (30)-C 90 , and C 1 (32)-C 90 ) are the largest empty-cage fullerenes to be structurally characterized in pristine form. [2,13] Larger fullerene cages have been structurally characterized for the endohedral fullerenes La 2 @D 5 A C H T U N G T R E N N U N G (450)-C 100 and Sm 2 @D 3d A C H T U N G T R E N N U N G (822)-C 104 . [14,15] Here we report the isolation of four isomers of C 96 and the structural characterization of two of these by single-crystal X-ray diffraction.…”

Molecular basis for the recognition of higher fullerenes into ureidopyrimidinonecyclotriveratrylene self-assembled capsules

“…In the case of C90, we choose its D5h isomer in virtue of its higher symmetry; we also note that this is the most abundant C90 isomer occurring in soot generated from Sm2O3-doped graphite rods. [26] To begin with (Table 1), C60 and C70 are independently considered inside all of the seven accessible capsule conformers (four homochiral, three meso, as explained earlier). However, for C76, C78, C84, and C90 complexes, investigation is subsequently limited to the five 12 conformers that are shown in Table 1 to yield the most favorable encapsulation energies with C70.…”

Silicon doping on nanotubular fullerene D5h–C90 from first principles

“…However, most recently a fullerene C 90 have been successfully isolated and characterized [11][12]. The obtained C 90 fullerene exhibits D 5h symmetry and a tubular shape according to the X-ray crystallographic study [12].…”