Cyclo-hexa-2,5-diene-1,4-dione-1,2,4,5-tetra-fluoro-3,6-diiodo-benzene (1/1).

The asymmetric unit of the title co-crystal adduct, C(6)H(4)O(2)·C(6)F(4)I(2), comprises a half-mol-ecule each of cyclo-hexa-2,5-diene-1,4-dione and 1,2,4,5-tetra-fluoro-3,6-diiodo-benzene. The C(6)F(4)I(2) mol-ecule is almost planar (r.m.s. deviation = 0.0062 Å). In the crystal, the components are connected through O⋯I halogen bonds [3.017 (11) Å], leading to the formation of wavelike chains along the a axis. The crystal packing also features C-H⋯F inter-actions.

2,4-Diiodo-3-nitro-anisole.

IN THE TITLE COMPOUND (SYSTEMATIC NAME: 1,3-diiodo-4-meth-oxy-2-nitro-benzene), C(7)H(5)I(2)NO(3), the dihedral angle between the benzene ring and the nitro group is 88.0 (3)°, and the methyl group lies almost in the same plane as the ring [deviation = 0.034 (6) Å]. In the crystal, aromatic π-π stacking occurs between inversion-related rings [centroid-centroid separation = 3.865 (3) Šand slippage = 0.642 Å]. A possible weak C-I⋯π inter-action occurs [I⋯π = 3.701 (2) Šand C-I⋯π = 130.18 (13)°], but there are no significant inter-molecular I⋯I contacts.