title: A third polymorph of 1,4-bis-(1H-benzimid-azol-2-yl)benzene.
abstract: The title compound, C20H14N4, is a new polymorph of the previously reported structures, which were ortho-rhom-bic, space group Pbca [Bei et al. (2000). Acta Cryst. C56, 718-719] and monoclinic, space group P21/c [Dudd et al. (2003). Green Chem. 5, 187-192]. The asymmetric unit consists of two independent mol-ecules in which the dihedral angels between the central benzene ring and the outer benzimidazole ring systems are 16.81 (10) and 14.23 (10)° in one molecule and 26.09 (10) and 37.29 (10)° in the other. In the crystal, mol-ecules are linked by N-H⋯N and C-H⋯N hydrogen bonds into a tape running along the c-axis direction.
authors.affiliation: Key Laboratory of Functional Organometallic Materials of General Colleges and Universities in Hunan Province, Department of Chemistry and Materials Science, Hengyang Normal University, Hengyang 421008, People's Republic of China.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Fu
authors.affiliation: Key Laboratory of Functional Organometallic Materials of General Colleges and Universities in Hunan Province, Department of Chemistry and Materials Science, Hengyang Normal University, Hengyang 421008, People's Republic of China.
authors.forename: Yan-Fei
authors.initials: YF
authors.lastname: Liang
authors.affiliation: Key Laboratory of Functional Organometallic Materials of General Colleges and Universities in Hunan Province, Department of Chemistry and Materials Science, Hengyang Normal University, Hengyang 421008, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Functional Organometallic Materials of General Colleges and Universities in Hunan Province, Department of Chemistry and Materials Science, Hengyang Normal University, Hengyang 421008, People's Republic of China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Zhu