The minor isomers and IR spectrum of [84]fullerene

One hundred and fifty four lines have been detected in 120 000 and 50 000 scan C-13 NMR spectra of main and tail HPLC fractions, respectively, of [84]fullerene. Five minor isomers are deduced to be present (in ca. 25% and 40% overall yields in the main and tail cuts, respectively), as well as the two main isomers [D-2(IV) and D-2d(II), which are present in a ratio of ca. 2.25:1]. A second D-2 isomer, which calculations predict to be D-2(III), is firmly established as one of the components, and the other isomers are indicated to be: D-3d, D-6h, C-5(IV), and either C-5(V) or C-2(IV). The relative proportions of the isomers differ-according to the HPLC fraction, and a partial elution order (Cosmosil Buckyprep/toluene) is D-3d/C-5(IV) < D-2(III)/D-6h. The IR spectrum of [84]fullerene does not correlate well with theoretical predictions.