In the first phase of this work, the basic C 60 and C 70 as well as the higher fullerenes, mainly C 76 and C 84 , were Soxhlet extracted with p-xylene and n-heptane from the samples of carbon soot, produced in electrical arc, yielding 5.9% and 0.7% of the extract, respectively. The remaining, p-xylene insoluble soot was then extracted with pyridine, by original advanced method, increasing the entire extract yield for an additional 5.9% to 11.8%. The procedures for increases of the basic and higher fullerenes yields, as well as for additional, selective extraction of the higher fullerenes were found. Chromatographic separation of the basic and the higher C 76 and C 84 fullerenes from p-xylene extract was performed by continual elution, in one phase of the process, under atmospheric pressure, with original, defined, gradient of solvents from 5% toluene in hexane to pure 100% toluene, on active Al 2 O 3 column, by a new, improved method. Identifications of the basic and the higher fullerenes in chromatographically purified fractions, as well as in the obtained extracts, were performed using determined techniques of IR and UV/VIS spectroscopy that have not been presented previously for the higher fullerenes.

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In the first phase of the process, the higher fullerenes, mainly C 76 and C 84 , as well as the basic fullerenes C 60 and C 70 , in a smaller amount, were Soxhlet extracted with pyridine from the sample of initial carbon soot, produced in electrical arc. The extract was obtained in increased, high yield of 16.4%, due to application of the original procedure. The solubility of fullerenes in this solvent was determined. Chromatographic separation of fullerenes from pyridine extract was performed by continual elution, in one phase of the process, under atmospheric pressure, with original, defined gradient of solvents, from pure hexane to pure toluene, on active Al 2 O 3 column, by a new, improved method. Identifications of fullerenes in the obtained chromatographically purified fractions and pyridine extract of the initial soot were performed using determined IR and UV/VIS techniques that have not been presented previously for the higher fullerenes.

The stable isomers of the higher fullerenes C 76 and C 84 with D 2 symmetry as well as the basic fullerenes C 60 and C 70 were isolated from carbon soot and characterized by the new and advanced methods, techniques, and processes. The validity of several semiempirical, ab initio, and DFT theoretical calculations in predicting the general pattern of IR absorption and the vibrational frequencies, as well as the molecular electronic structure of the C 76 and C 84 isomers of D 2 symmetry, is confirmed, based on recent experimental results. An excellent correlation was found between the previously reported theoretical data and the recently obtained experimental results for these molecules over the relevant spectral range for the identification of fullerenes. These results indicate that there are no errors in the calculations in the significant spectral regions, the assumptions that were based on previous comparisons with partial experimental results. Isolated fullerenes are important for their applications in electronic and optical devices, solar cells, optical limiting, sensors, polymers, nanophotonic materials, diagnostic and therapeutic agents, health and environment protection, and so forth.

The basic and the higher fullerenes were chromatographically isolated from the obtained series of carbon soot extracts, in increased yields, by the new, advanced methods, on Al2O3 columns. The elution was performed continuously, in one phase of each process, at ambient conditions, with the several different original hexane-toluene gradients. Various separation systems were used previously. The unique and the main, dominant absorption maxima of the purified higher fullerenes were registered in the spectral regions where they intensively absorb, applying the IR and UV/VIS techniques. All the observed absorption bands are in excellent agreement with theoretical calculations, indicating the achieved advancement in chromatographic separation and spectroscopic characterization. The isolated fullerenes are important for investigation of their remarkable optical and electronic properties, as well as for the numerous possible applications in chemistry, physics, biomedicine, diagnostic and therapeutic agents, sensors, polymers, nanophotonic materials, special lenses, optical limiting, organic field effect transistors, solar cells etc.