title: 4-Chloro-2-[(E)-(4-nitro-phen-yl)diazenyl]phenol.
abstract: The title compound, C(12)H(8)ClN(3)O(3), in the crystalline state and in solution, exists in the azo form, as predicted by density functional theory (DFT) calculations. The mol-ecule is approximately planar [the dihedral angle between the rings is 1.83 (8)°], with the nitro group slightly twisted [13.4 (2)°] relative to the benzene ring. Translationally related mol-ecules form stacks along [010] with an inter-planar distance of 3.400 (2) Å. The hydroxy group forms an intramolecular hydrogen bond with the azo N atom.
authors.affiliation: Department of Chemistry, Moscow State University, 119992 Moscow, Russian Federation.
authors.forename: Leonid A
authors.initials: LA
authors.lastname: Aslanov
authors.forename: Ksenia A
authors.initials: KA
authors.lastname: Paseshnichenko
authors.forename: Alexandr V
authors.initials: AV
authors.lastname: Yatsenko