Место издания:Lobachevsky State University of Nizhni Novgorod Nizhni Novgorod
Первая страница:162
Аннотация:Investigations of thermodynamic properties of trifluoromethylfullerenes are significantly hampered by the fact that preparation of pure compounds in amounts required for thermodynamic studying is a rather difficult task. But in this work a trifluoromethylfullerene S6-С60(CF3)12 was synthesized using a
three-section glass ampoule in gramme-scale amount sufficient for reliable experimental investigation. Sample of S6-С60(CF3)12 was characterized by elemental analysis, IR, UV/Vis, NMR 19F, Raman spectra and X-ray powder diffraction data.
The energy of combustion of S6-С60(CF3)12 in oxygen was determined in a rotating-bomb isoperibolic calorimeter. The heat capacity of S6-С60(CF3)12 was determined in a
fully automated set-up a vacuum adiabatic calorimeter. This system was also used for
processing and collecting the heat capacity data. We determined the enthalpy of combustion of S6-С60(CF3 )12 in oxygen and its heat capacity, which made possible to derive the thermodynamic functions of S6-С60(CF3)12, namely enthalpy, entropy and Gibbs energy of formation at 298.15K. The enthalpy of formation of C60(CF3)n , n = (2–18) were estimated by method of isodesmic reactionsical data enabled estimation of the formation energy for a broad range of other trifluoromethylated compounds C60(CF3)n, with n = (2–18), on the basis of their DFT calculated relative energies.