C₆₀·Bromobenzene Solvate:  Crystallographic and Thermochemical Studies and Their Relationship to C₆₀ Solubility in Bromobenzene

Abstract

Differential scanning calorimetry, solution calorimetry, and room-temperature single-crystal X-ray diffraction were used to study the thermodynamic and structural properties of a solvated crystal C60·2C6H5Br. In the monoclinic solvate, two orientations of C60 were observed with fractional populations of 0.71 and 0.29. The enthalpy of solution of pure C60 in bromobenzene was determined to be Δsol H[C60(s)] = −11.5 ± 2.0 kJ/mol. The enthalpy of solution of the solvated crystal was Δsol H[C60·2C6H5Br(s)] = +28 ± 1 kJ/mol. The phase diagram of the system C60−C6H5Br for T < 423 K was constructed. It predicts the existence of a maximum in the temperature−solubility relationship for C60 in bromobenzene at 350 K. The activity of bromobenzene vapor over the solvated crystal is predicted to be reduced from its value over the pure liquid by a factor of 3.5.

Material Solubility‐Photovoltaic Performance Relationship in the Design of Novel Fullerene Derivatives for Bulk Heterojunction Solar Cells

“…Nonetheless, there are several reports in the literature, where it was demonstrated that the solubility of fullerene-based compounds depends on the composition, the crystal structure, and the thermodynamic stability of ''solvates'' that are formed in the system. [31][32][33][34] Solvates are Van der Waals adducts of solutes (dissolved compounds) with solvents. In the simplest case, solubility is determined by the equilibrium of the system schematically outlined in Scheme 2, where ''S'' denotes the solvent molecules.…”

Higher fullerenes: Compositional analysis by EDXD and molecular dynamics

“…fullerenes of a single size. We probed models of all sizes that were, to our knowledge, resolved, hence with available structural coordinates: C60 [19], C70 [20], C74 [21], C76 [22], C80 [23], C82 [24], C84 [25], C90 [26], C96 [27]. Furthermore, a simulation with the hypothesized structure of fullerene C180 [28] was made, using the cartesian coordinates published in the webpage http://www.nanotube.msu.edu/fullerene/fullerene-isomers.html.…”

The solubility of light fullerenes in styrene over the temperature range 20–80°C

“…2), the solubility polytherm is an S-shaped curve; this is evidence that the solid phase at equilibrium with the saturated solution is nonsolvated ë 70 fullerene (otherwise, a nonmonotonic temperature dependence of solubility is as a rule observed [8][9][10][11][12]). The absence of crystallization styrene in the solid phase with pure fullerene ë 70 was also proved experimentally.…”