Single-Crystal X-ray Diffraction Studies of Solvated Crystals of C 60 Reveal the Intermolecular Interactions between the Component Molecules

Abstract

The solid-state structures of seven solvates of C 60 (C 60 ·4tetrachloroethylene, C 60 ·2tetrachloroethylene, C 60 ·3benzene, C 60 ·n-pentane, C 60 ·diethyl ether, C 60 ·chlorobenzene, and C 60 ·benzene·dichloromethane) were determined by single-crystal X-ray diffraction at low temperature. At 90 K, the fullerene and solvate components are generally well-ordered and do not show the orientational disorder that plagues similar structures determined at room temperature. Interactions between the solvate molecules and the fullerene and between adjacent C 60 molecules were examined and analyzed. Van der Waals and weak charge-transfer interactions are important to help to organize the individual components in these structures. The weak Lewis acid behavior of C 60 , such as when it cocrystallizes with diethyl ether or chlorinated solvents, is apparent. In addition, π-stacking interactions are prevalent. The solvates of C 60 reported here were frequently obtained from attempts to cocrystallize C 60 with another chemical compound. Although the desired cocrystals were never formed, the unincorporated molecules influenced solvate formation.