An Evaporation Study of C76 by Knudsen Cell Mass Spectrometry

O.V. Boltalina, V.Yu. Markov, A. Ya. Borschevskii, V. L.N. Sidorov, V. N. Bezmelnitsin, A. V. Eletskii and R. Taylor

Rapid Commun. Mass Spectrom., v. 12, pp. 1028-1030, (1998)

ABSTRACT. The vapour pressure of pure C76 and its sublimation enthalpy have been determined by Knudsen cell mass spectrometry in the temperature range 637-911 K. The temperature-pressure equation is ln(p/Pa)=(- 22806+-820)/T(K) + (24.52+-1.08). The mean sublimation enthalpy at 764 K is (190+-7) kJ*mol-1 This value is lower than that, (222+-17) kJ*mol-1, determined by us previously from a mixture of higher fullerenes, confirming further that the mixture of higher fullerenes is not an ideal solid solution.

Laboratory of Thermochemistry