The structure of solid carbon tetrafluoride

Abstract

Abstract The structure of phase II of CF4 has been refined in the monoclinic space group C2/n (No. 15) from high-resolution powder neutron diffraction data. At 1.5 K the lattice parameters are a = 8.4098(2) Å, b = 4.3022(1) Å, c = 8.3506(2) Å, and β = 119.588(1)°, Z = 4. An error in the table of coordinates in the original report of the structure, which was improperly corrected in a subsequent paper, has been rectified. The refined structure of phase II is in excellent agreement with recent theoretical calculations of the crystal static energy and molecular dynamics simulations. The unit cell of the orientationally disordered phase I has been indexed as rhombohedral, a = 11.577(9) Å, α = 89.49(1)° at 80 K. It is likely that this phase is isostructural with phase Ib of CCl4.