Structures of polyfluoroaromatic compounds. Part VI [1]. Crystal structure of 3H,3′H-4,4′-dinitrohexafluorodiphenyl sulphide

Crystals of the title compound are tetragonal, with unit cell dimensions a = b = 6.10(1), c = 37.16(2) Å, space group P4₁2₁2. The structure has been determined from 780 three-dimensional counter data and refined to a value of 4.5% for the conventional discrepancy factor R. Estimated standard deviations average 0.006 Å for bond lengths and 0.5° for bond angles. The molecule has C₂ symmetry. The symmetry-related aromatic rings are each inclined at an angle of 61° to the C-S-C plane. The length of the C-S bond, 1.771(4) Å, corresponds closely to that expected for a single bond between sulphur and sp²-hybridized carbon. The bond angle at sulphur is 99.7(3)°, some 4° smaller than the angle in unfluorinated diaryl sulphides.