Effect of C
Fullerene on the Boiling Point
of Its Solutions in Some Aromatic Solvents
B. M. Ginzburg, Sh. Tuichiev, and S. Kh. Tabarov
Institute of Machine Building Problems, Russian Academy of Sciences, St. Petersburg, Russia
Tajik State National University, Dushanbe, Tajikistan
Received March 17, 2008
Abstract—Concentration dependences of the boiling points T
fullerene solutions in four aromatic
solvents were determined. For benzene and p-xylene, processing of the increasing dependence in terms of the
Raoult law enabled estimation of the cooperativity parameters of the interaction between fullerene and solvent
ISSN 1070-4272, Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 3, pp. 387–390. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © B.M. Ginzburg, Sh.Tuichiev, S.Kh. Tabarov, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 3, pp. 395–398.
The aim of our study was to determine the
concentration dependences of the boiling point of C
solutions in a series of four aromatic solvents:
benzene, toluene, p-xylene, and 1,2-o-dichlorobenzene
(DCB). It was found that the run of these dependences
is governed by the symmetry of the solvent molecules.
Among the mentioned molecules, that of benzene is
the most symmetric. It has a sixth-order rotation axis
passing through the center of the molecule
perpendicularly to its plane and six symmetry planes
passing in pairs through atoms in para-positions (three
planes) and through mid-points of the C–C bonds,
arranged opposite one another (three more planes).
In the case of toluene, the situation changes
dramatically. The toluene molecule has only a single
element of symmetry, which is the symmetry plane
passing perpendicularly to the plane of the benzene
ring through its center and the carbon atom of the
methyl group. Apparently, the symmetry of the p-
xylene molecule is higher than that of the toluene
molecule: there are two symmetry planes and one
second-order rotation axis. In the case of DCB, the
symmetry of the molecule is as low as that of toluene.
Presumably, the symmetry of the solvent molecules
affects their interaction with C
which, in the end, is manifested in the run of the
concentration dependences of the boiling points. Some
parameters of the solvents studied are listed in Table 1.
We chose for experiments the Sivolobov method
 developed for determining the boiling point in
comparatively small volumes.
We prepared the solutions to be studied from C
fullerene (99.7% purity) produced by the Kratschmer–
Huffman method  and solvents of chemically pure
grade subjected to distillation. First, the mother liquor
of a preliminarily known limiting concentration c
(%) was prepared. Then, this mother liquor was diluted
to obtain solutions with intermediate concentrations.
The concentrations of the solutions were varied from
% (here and hereinafter the concentrations are
given in weight percent) to concentrations close to that
of a saturated fullerene solution. The determination
errors for the lowest and highest concentrations were
1–2% and ≤0.1–0.2%, respectively.
We made 10 to 30 measurements of the boiling
for samples of each concentration. The
measurement error ±Δt was found using the formula
∆t = Т
is the standard error of a result of N
measurements, and T
is the Student coefficient whose
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