Geometries for the CH3F...CH3F complex and monomers were obtained from the
X40 set of noncovalent interactions of halogenated molecules from
  J. Řezáč, K.E. Riley, and P. Hobza, J. Chem. Theory Comput. 8, 4285 (2012).

Simulation cell lattice vectors / angstroms:

20.255526 0.000000 0.000000
0.000000 20.299986 0.000000
0.000000 0.000000 24.181228

