The title 4,4'-disubstituted diphenyl-1,3-triazines, C14H15N3, (I), C12H9ClFN3, (II), and C13H12FN3, (III), each contain a triazene group (-N=N-NH-) having an extended conformation. The dihedral angles between the two benzene rings in (I), (II) and (III) are 4.3, 3.4 and 6.5 degrees , respectively. The molecules are almost entirely planar, with maximum deviations from the mean planes of 0.1087 (2), -0.1072 (7) and 0.1401 (3) A, respectively. In each compound, the molecules are linked by N-H...N hydrogen bonds to form chains and pack similarly in the crystal structures.

Key indicatorsSingle-crystal X-ray study T = 180 K Mean '(C±C) = 0.005 A Ê R factor = 0.069 wR factor = 0.195 Data-to-parameter ratio = 10.2 For details of how these key indicators were automatically derived from the article, see

Key indicatorsSingle-crystal X-ray study T = 180 K Mean '(C±C) = 0.005 A Ê Disorder in main residue R factor = 0.063 wR factor = 0.191 Data-to-parameter ratio = 9.5For details of how these key indicators were automatically derived from the article, see

Key indicatorsSingle-crystal X-ray study T = 296 K Mean (C-C) = 0.003 Å R factor = 0.034 wR factor = 0.061 Data-to-parameter ratio = 13.1 For details of how these key indicators were automatically derived from the article, see

Key indicatorsSingle-crystal X-ray study T = 296 K Mean (C-C) = 0.004 Å R factor = 0.038 wR factor = 0.059 Data-to-parameter ratio = 14.1 For details of how these key indicators were automatically derived from the article, see A view of (I), showing the atomic numbering scheme and 50% probability displacement ellipsoids. The intramolecular hydrogen bond is shown as a dashed line.