Room-temperature compressibility ofC60: Intercalation effects with He, Ne, and Ar

Abstract

Rapid Communications are intended for the accelerated publication of important new results and are therefore given priority treatment both in the editorial offtce and in production AR. apid Communication in Physical Review 8 should be no longer than four printed pages and must be accompanied by an abstract Pag. e proofs are sent to authors.We report measurements to 6 kbar of the room-temperature compressibilities of C60 for both the fcc and sc phases using He, Ne, and Ar as pressure media. The effects of rare-gas intercalation on the fcc-to-sc transition and on the compressibilities are discussed and we compare our results with the widely disparate literature values reported for the fcc compressibility.

Helium penetrates into silica glass and reduces its compressibility

“…However, it should be used with caution. In fact, it is well known that gas atoms penetrate into microporous crystals (that is, crystals having larger voids with a diameter up to 20 Å), such as fullerenes 31 , zeolites 32 , and clathrates 33 , and affect their compression behaviour. Our results suggest the possibility that helium may cause (or may have caused) some problems also in experiments on ordinary materials with voids.…”

Dynamics of CO Molecules in SolidC60as a Function of Cavity Size

“…The sample chamber is a small 0.5 mm diameter hole drilled in a brass gasket that is preindented down to approximately 30 mm thickness. No pressure transmitting medium is used or needed as C 60 may be seen to act as a perfect pressure transmitting medium itself [7] and as intercalation of C 60 with species other than CO needs to be avoided in this study [8]. The high-pressure cell is of the type as described by others [9] and consists of two identical 6.35 mm diameter sapphire balls on which facets of approximately 1.5 mm diameter are polished perpendicular to the c axis.…”

Hysteretic phenomena in Xe-doped C60 from x-ray diffraction

“…This circumstance was utilized at the very beginning of the fullerene era resulting in the high-T c superconductivity of an organic crystal (C 60 doped with alkali metals) [1]. Afterwards, C 60 was intercalated with rare gas atoms [2][3][4][5][6][7] and molecules of different symmetries and sizes [8][9][10][11][12][13][14]. It is commonly accepted that changes in the physical properties of fullerite C 60 brought about by intercalation with neutral species are mainly due to the doping-related change in the molar volume.…”