The density of the cubic C-60-CCl4 solvated crystal was measured to be
1.77 +/- 0.01 g cm(-3) at 20 degrees C by the buoyancy method. The de
nsity and lattice constant, a = 27.38 Angstrom, confirm that the cryst
al is composed of a C-60(CCl4)(13) formula unit. The AB(13) type struc
ture known in binary alloy and colloid systems is proposed for this so
lvated crystal.