title: A second monoclinic polymorph of N-(2,4-dinitro-phen-yl)-2,4-dinitro-aniline.
abstract: The title compound, C(12)H(7)N(5)O(8), was previously described in space group P2(1)/n with Z = 4 [Wu et al. (2007 ▶). Acta Cryst. E63, o4194]. The current monoclinic P2(1)/c polymorph was obtained from a mixed solution of dichloro-methane and hexane. The dihedral angle between the benzene rings is 44.16 (5)°, smaller than in the previously reported polymorph [56.3 (2)°]. As a result of the steric hinderance of the nitro groups, hydrogen bonding is limited intramolecularly. The dihedral angles between the phenyl rings and their attached nitro groups are 18.97 (6) and 17.71 (5)° at the 2-position, and 18.52 (6) and 32.41 (6)° at the 4-position.
authors: Department of Material Science and Chemistry, Wakayama University, Sakaedani, Wakayama, 640-8510,  Japan.
authors: Yui
authors: Y
authors: Tokutome
authors: Tsunehisa
authors: T
authors: Okuno