A second ortho­rhom­bic polymorph of 3,5-diphenyl-4H-1,2,4-triazol-4-amine

The present crystal structure is the second ortho­rhom­bic polymorph of the title compound, C(14)H(12)N(4). Whereas the structure in Pnma with Z′ = 0.5 is already known [Ikemi et al. (2002 ▶). Heterocycl. Commun. 8, 439–442], the present structure crystallizes in the space group Pbca with Z′ = 1. The dihedral angle between the two phenyl rings is 23.5 (4)° and the dihedral angles between central ring and the phenyl rings are 41.0 (3) and 26.3 (5)°. In the 4-amino-1,2,4-trizole fragment, the C=N distances are 1.321 (3) and 1.315 (3) Å, which are much shorter than the C—N distances of 1.367 (3) and 1.357 (3) Å. In the crystal, adjacent mol­ecules are linked by N—H⋯N hydrogen bonds.