Amorphous shungite carbon: A natural medium for the formation of fullerenes

A comparative analysis of data on the density, porosity, and intermolecular space of high-carbon shungites, graphite, glassy carbon, and C-60 fullerit e gave an estimate of the fullerene content in the shungite samples which a grees with the values obtained by electrochemical and polar solvent extract ion methods. A low yield of fullerenes in the extracts obtained with nonpol ar solvents is explained by the high polarity and large adsorption energy o f fullerenes and related compounds. (C) 2000 MAIK "Nauka/Interperiodica".