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One of the more interesting recent discoveries in the field of fullerene compounds are the fullerene-cubane rotor-stator compounds (Pekker et al., Nature Materials 4, 764 (2005)). In these compounds the cubane molecules (C8H8) sit in the octahedral interstitial sites between the fullerene molecules, and for geometric reasons they are orientationally fixed in the slightly expanded face centered cubic fullerene lattice. The fullerenes, on the other hand, are free to rotate between between these "molecular bearings", and as a result of the decreased interfullerene interaction the rotational transition temperature is significantly decreased (for C60, from 260 K for pure C60 to 140 K). Heating results in cubane breakdown and intermolecular reactions such that a copolymer is formed. We have already reported that at least two different such polymers, plus at least one carbon-rich high-temperature phase, are formed at high pressures, and we have mapped the reaction and phase diagram to 900 K and 2 GPa. Here, we present further data 1) for the low temperature fluorescence properties of cubane-C60, showing that the C60 molecules behave much like free molecules due to the very weak intermolecular interactions, and 2) for the structural properties of the carbon-rich structures formed on heating to high temperatures under pressures from zero (vacuum) to 2 GPa. |