Binary Solid Solution of C₆₀-C₇₀ Prepared by Volatilization Method

Abstract

  C₆₀-C₇₀ solids were prepared via volatilization of solutions of C₆₀ and C₇₀ in toluene as the solvent. During volatilization of the toluene, saturated fullerene molecules did not precipitate as a C₆₀-C₇₀ solid, but formed a single phase (C₆₀)_1−x(C₇₀)_x•C₆H₅CH₃ solvate. The solvate was unstable in air when x was small and naturally decomposed into a C₆₀-C₇₀ solid. With heat-treatment in a vacuum, the solvate could also be converted into the C₆₀-C₇₀ solid even when x was large. The single solvate phase produced two phases of C₆₀-C₇₀ solids, indicating that the C₆₀-C₇₀ system possesses a miscibility gap.