Key indicators: single-crystal X-ray study; T = 100 K; mean (C-C) = 0.002 Å; R factor = 0.044; wR factor = 0.134; data-to-parameter ratio = 44.7.The title compound, C 13 H 8 Cl 2 O 2 , crystallizes with two independent molecules in the asymmetric unit. Each of the two unique molecules is twisted about the C-C single bonds, making dihedral angles of 24.29 (5) and 73.01 (5) between the two rings. In the crystal structure, the molecules are interlinked into columns along the b axis by intermolecular O-HÁ Á ÁO and C-HÁ Á ÁO interactions and short ClÁ Á ÁCl and OÁ Á ÁCl contacts. In addition, the crystal packing is further stabilized by weak C-HÁ Á Á interactions.
Related literatureFor related literature on hydrogen-bond motifs, see: Bernstein et al. (1995). For related literature on values of bond lengths, see: Allen et al. (1987). For related structures, see: Harrison et al. Experimental Crystal data C 13 H 8 Cl 2 O 2 M r = 267.09 Triclinic, P1 a = 7.8450 (2) Å b = 12.1815 (3) Å c = 12.9442 (3) Å = 73.087 (1) = 80.468 (1) = 77.869 (1) V = 1149.83 (5) Å 3 Z = 4 Mo K radiation = 0.55 mm À1 T = 100.0 (1) K 0.69 Â 0.14 Â 0.13 mm Data collection Bruker SMART APEX II CCD area-detector diffractometer Absorption correction: multi-scan (SADABS; Bruker, 2005) T min = 0.851, T max = 0.932 45186 measured reflections 14083 independent reflections 10281 reflections with I > 2(I) R int = 0.045