The crystal structure of 2′,6′-dichloro-4-dimethylaminoazobenzene

A monoazo dye, 2', 6'-dichloro-4-dimethylaminoazobenzene (C14H13Cl2N3) was synthesized and characterized by X-ray diffraction, IR, H-1 NMR, and elemental analysis. The title molecule crystallizes in the monoclinic system space group P2(1)/c (#14), a = 10.782(1), b = 8.9610(9), c = 15.108(2) angstrom, beta = 103.008(5)degrees, V = 1422.2(3) angstrom(3), Z = 4. The title molecule is not planar and takes trans-geometry and the two phenyl rings are twisted around the central linkage in opposite directions. In the crystal, molecules are interacted through pi(...)pi interaction, forming 'double chains' along [1 -1 0]. The 'double chains' are extended along [001] through H-Bond C11-H6(...)C12, C5-H3(...)C11 forming double layers (110), which are in turn interacted by C3-H1(...)C11 H-Bond [010], forming crystals. The molecular geometry has been calculated using the ab initio restricted Hartree-Fock and density functional method (B3LYP) with 6-311G** basis set. The optimized geometric parameters obtained by two methods are similar and in good agreement with the experimental values. (c) 2005 Elsevier Ltd. All rights reserved.