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

Autor: Korobov, M. V., Mirakian, A. L., Avramenko, N. V., Valeev, E. F., Neretin, I. S., Slovokhotov, Y. L., Smith, A. L., Olofsson, G., Ruoff, R. S.
Zdroj: The Journal of Physical Chemistry - Part B; May 7, 1998, Vol. 102 Issue: 19 p3712-3717, 6p
Abstrakt: 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 ΔsolH[C60(s)] = −11.5 ± 2.0 kJ/mol. The enthalpy of solution of the solvated crystal was ΔsolH[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.
Databáze: Supplemental Index