Fullerenes in solutions
Phenomena and processes related to the behavior of fullerenes in solutions are reviewed. Data on the solubility of C60 and C70 fullerenes in a large number of solvents at various temperatures are presented as well as on diffusion coefficient of fullerenes in solutions. The relation between the factors controlling the behavior of dissolved fullerenes and the clustering tendency they show is analyzed. This tendency, which sets fullerenes apart from other large molecules, underlies many aspects of fullerene behavior in solutions, such as the recently discovered nonmonotone temperature dependence of fullerene solubility in various solvents, the nonlinear concentration dependence of nonlinear optical susceptibility, the sharp dependence of the color of a fullerene solution on the solution composition (the solvatochromatic effect), the concentration dependence of the heat of solution of fullerenes in organic solvents, etc. Growth mechanisms of fractal clusters in fullerene solutions are analyzed along with similarity laws determining the thermodynamic characteristics of fullerite crystals.