Separation, isolation and characterisation of two minor isomers of the [84]fullerene C84

Endohedral chemical shifts in higher fullerenes with 72-86 carbon atoms

“…These assignments are consolidated by our calculations since they are the lowest-energy isomers among the structures of the given symmetry. The other C 2 isomer detected by Tagmatarchis et al [13] might be the second most stable C 2 isomer, C 84 :8, according to our calculations. Concerning the minor D 2 isomers, one of them was assigned to C 84 : 21 by combining the computed energy order (at the MNDO level) and the 13 C NMR spectra [15].…”

“…structure of this doped species was interpreted to have C 2v symmetry [43,44]. The bare C 82 cluster was isolated by Tagmatarchis et al [13] and Dennis et al [14] and also was observed by Wang et al [17], but a detailed characterization for the bare cluster has not been achieved so far. According to the 13 C NMR spectra, three isomers of C 82 were identi®ed to be of C 2 symmetry [6].…”

“…In this way, two of the ®ve mathematically possible C s isomers have been assigned to C 84 :15 and C 84 :16 [15] and one of the ®ve possible C 2 isomers to C 84 :11 [13,15]. These assignments are consolidated by our calculations since they are the lowest-energy isomers among the structures of the given symmetry.…”

“…There are 24 structural isomers of C 84 that obey the IPR [28]. Two main isomers, D 2 (C 84 :22) and D 2d (C 84 :23) [12], and four minor isomers, D 6h (C 84 :24) and D 3d (C 84 : 19) [13], D 2d (C 84 :4) and D 2 (C 84 :5) [14], have been isolated and characterized by their 13 C NMR spectra. Other isomers have also been observed experimentally, including two C 2 [13], two C s and one of unassigned symmetry [14].…”

Communication: Fullerene resolution by the magnetic circular dichroism

“…[2][3][4][5][6][7][8][9][10] Typically, high performance liquid chromatography (HPLC) coupled with 13 C nuclear magnetic resonance (NMR) or mass spectrometry is used for their analysis. [11][12][13][14] However, their discrimination is complicated due to their similar physical properties. Fullerene shapes are close to a sphere or ellipsoid, and often exhibit a high degree of symmetry.…”