The structure of $\left(\mathrm{CO}{)}_x{\mathrm{C}}_{60}\mathrm{}\right(x=0.67\mathrm{})\mathrm{}$ has been determined by x-ray powder diffraction at 25 K. CO is found distributed over six equivalent orientations on the octahedral sites of the cubic close-packed structure of ${\mathrm{C}}_{60}.$ The ${\mathrm{C}}_{60}$ molecules are orientationally ordered in almost exclusively the major orientation. Evidence is presented for a weak electrostatic interaction between ${\mathrm{C}}_{60}$ and CO.

• Received 5 September 1997

DOI:https://doi.org/10.1103/PhysRevB.57.6321