Formation and Properties of C70 Solidlike Species in Room-Temperature Solutions

Abstract

Recently, studies of fullerene molecules, especially C{sub 60} and C{sub 70}, have attracted great attention. Many fascinating and sometimes unusual properties, such as formation of complexes between fullerene and solvent molecules in the solid state and significant discrepancies between calculated and experimental electronic transition probabilities in both C{sub 60} and C{sub 70}, have been observed. It was reported that C{sub 70} undergoes anomalous solvatochromic changes in room-temperature solvent mixtures. The characteristic phenomena were attributed to the formation of new absorbing species. In this communication the authors report a spectroscopic study of the characteristic solvatochromic behavior of C{sub 70} in room-temperature mixtures of toluene and acetonitrile. It will be shown that the formation of the new absorbing species of C{sub 70} responsible for the anomalous solvatochromism depends not only on the concentration of C{sub 70} and the composition of the solvent mixtures but also on the way in which the solvent mixtures are prepared. Microstructures of the new absorbing species will be discussed. 11 refs., 2 figs.