Bis(4′-hydroxybiphenyl-4-carboxylato-κO 1)(1,10-phenanthroline-κ2 N,N′)zinc

In the title compound, [Zn(C13H9O3)2(C12H8N2)], the ZnII atom is located on a twofold rotation axis and has a distorted tetrahedral coordination with two N atoms from the phenanthroline ligand arranged around the twofold axis and two O atoms from two symmetry-related 4′-hydroxybiphenyl-4-carboxylate ligands. The molecules are linked by O—H⋯O hydrogen bonds, forming a chain developing parallel to [101].

In the title compound, [Zn(C 13 H 9 O 3 ) 2 (C 12 H 8 N 2 )], the Zn II atom is located on a twofold rotation axis and has a distorted tetrahedral coordination with two N atoms from the phenanthroline ligand arranged around the twofold axis and two O atoms from two symmetry-related 4 0 -hydroxybiphenyl-4-carboxylate ligands. The molecules are linked by O-HÁ Á ÁO hydrogen bonds, forming a chain developing parallel to [101].
interest for assembling coordination architectures. As a versatile ligand, it contains two sulfonic groups and two hydroxyl groups, which may be partially or completely deprotonated and normally serves as linkage to construct diverse metallosupramolecular systems (Song et al., 2004;Liu et al., 2011a). On the other hand, 1, 10-Phenanthroline, as one kind of those ligand, has usually been used to construct a great variety of structurally interesting entities, such as monomers (Breneman et al. 1993;Liu et al., 2011b, Zhang et al., 2011. Herein, we are interested in self-assemblies of Zn II ion with H 2 L and phen, which led to the title compound. The title compound, {[Zn(L) 2 (phen)] (H 2 L=4'-hydroxybiphenyl-4-carboxylic acid), is built up from a distorted tetrahedral Zn II located on a two fold axis and surrounded by two O atoms of two 4'-hydroxybiphenyl-4-carboxylate ligands and the two N atoms of the phenanthroline ligand (Fig. 1).  Table 1).

Refinement
All H atoms attached to C and O (hydroxyl group) atoms were fixed geometrically and treated as riding with C-H = 0.93 Å and O-H = 0.82 Å with U iso (H) = 1.2U eq (C, O).

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.