Polymorph of 4-(carbazol-9-yl)benzo­nitrile

The asymmetric unit of the title compound, C₁₉H₁₂N₂, contains two independent mol­ecules with a similar structure. In the two mol­ecules, the dihedral angles between the carbazole ring system and the benzene ring are 47.9 (5) and 45.4 (4)°, similar to the value of 47.89 (6)° found in the previously reported structure [Saha & Samanta (1999). Acta Cryst. C55, 1299–1300]. In the crystal, there is a weak C—H...N hydrogen bond between the two independent mol­ecules.

3,6-Diiodo-9H-carbazole

In the title compound, C₁₂H₇I₂N, the tricyclic aromatic ring system is essentially planar, with an r.m.s. deviation of 0.0272 Å. The two I atoms are marginally out of plane, with the C-I bonds angled at 3.9 (2) and 1.1 (2)° with respect to the planes of their respective benzene rings, above and below the plane of the carbazole ring system. No classical hydrogen bonds are observed in the crystal structure.