Phase diagram of model C _{<i>n</i> ⩾ 70} fullerenes

Abstract

Recent studies have confirmed that model C60 has a stable liquid phase confined to a rather narrow temperature range; in this letter we determine the phase diagram of model C70 and show that also this fullerene possesses a liquid phase whose existence range is wider than that of C60. A "corresponding state"behaviour of C60 and C70, emerging from a description in terms of reduced quantities of both the interaction potential and the phase diagrams' parameters, is then extended to higher-order fullerenes. Critical- and triple-point densities and temperatures of C76, C84 and C92 are thereby predicted. The decreasing accuracy of such a representation of Cn > 70 phase behaviour with increasing n is discussed in relation to the model potential features.