The preparation of novel fullerene-containing compounds C,&16~0.5CsH&l and Cso*0.5CsH&l is described. The spectral properties of the compounds and their thermal stabilities are studied. It is concluded that the Cso*O.SCsHsCl clathrate is a true van der Waals solid, while the CsoS16-0.5CsH&l is a complex bonded by weak charge-transfer interactions.
1. Intro4luction
The availability of fullerenes in large quantities has triggered an explosive research effort, particularly on the preparation of their derivatives, so-called fullerites. Recently, a new family of &,, compounds, which combine fullerene molecules with sulfur rings, Ss, have been synthesized [ l-3 1. Roth and Adelmann have reported on the preparation of a new fullerenecontaining van der Waals compound CsoSla [ 11. Lately, the solvent-containing sulfur-fttllerites C6&CS2 [ 21 and ( C60)6Ss,,CzHCls [ 31 have been obtained. The former is orthorhombic and shows a framework structure with S8 rings and CS2 dumbbells filling the channels; the latter is orthorhombic too. From UV-VIS-NIR-IR and EPR investigations it is known that (C60)6SBOClHClJ is a van der Waals solid without strong interactions between the constituent molecules [ 3 1.
On the other hand, the precipitation of CeO from organic solvents often results in solvent-containing crystals with low symmetry structures [4-61. Compounds of CsO containing different solvent molecules in an ordered fashion are clathrates, inclusion compounds without chemical interaction between the constituents. CsoX,, clathrates with various guest molecules, X, have been prepared and characterized