catena-Poly[[diaquabis(diphenylacetato)zinc(II)]-μ-4,4′-bipyridine]

In the title compound, [Zn(C14H11O2)2(C10H8N2)(H2O)2]n, the ZnII ion lies on a crystallographic inversion center and is in a slightly distorted octahedral coordination enviroment. 4,4′-Bipyridine ligands act as bridging ligands, connecting ZnII ions into a chain along the b-axis direction. In the crystal structure, these chains are linked by intermolecular O—H⋯O hydrogen bonds to form a two-dimensional network parallel to the ab plane.

In the title compound, [Zn(C 14 H 11 O 2 ) 2 (C 10 H 8 N 2 )(H 2 O) 2 ] n , the Zn II ion lies on a crystallographic inversion center and is in a slightly distorted octahedral coordination enviroment. 4,4 0 -Bipyridine ligands act as bridging ligands, connecting Zn II ions into a chain along the b-axis direction. In the crystal structure, these chains are linked by intermolecular O-HÁ Á ÁO hydrogen bonds to form a two-dimensional network parallel to the ab plane.

catena-Poly[[diaquabis(diphenylacetato)zinc(II)]-µ-4,4′-bipyridine]
Shan-Shan Yu, Hong Zhou, Hua Xian and Zheng-Fang Tian S1. Comment During the past decade, the design of new metal-organic supramolecular solids has attracted attention in the fields of coordination chemistry and crystal engineering, for the sake of developing desired crystalline materials with potential functionality (Moulton & Zaworotko, 2001;Janiak , 2003). Furthermore, it has been realised that weak noncovalent interactions such as hydrogen bonds, aromatic stacking, and van der Waals forces (Hosseini, 2005;Nishio, 2004) are crucial in the direction of such crystalline architectures. Hitherto, a variety of organic connectors containing pyridyl and/or carboxylate groups (Brammer, 2004) have been widely used to construct metal-organic supramolecular frameworks. Herein we report the crystal structure of the title compound (1).
The asymmetric unit of (I) is illustrated in Fig. 1. The structure of (I) is a one-dimensional chain (Fig. 2), in which the Zn II ions are coordinated by two O atoms from two monodentate carboxylate groups of two bis(diphenylacetato) ligands, two N atoms of two bridging 4,4′-bipyridine ligands and two O atoms from two water molecules. The Zn II ion is in a slightly distorted octahedral coordination environment. In the crystal structure, these one-dimensional chains are linked via intermolecular O-H···O hydrogen bonds to form a two-dimensional network.

S3. Refinement
The C-bound H atoms were placed to the bonded parent atoms in geometrically idealized positions (C-H = 0.93, and 0.98 Å) and refined as riding atoms, with U iso (H) = 1.2U eq (C). The O-bound H atoms were located in difference Fourier maps and refined as riding in their as-found positions but with O-H = 0.96 Å and with U iso (H) = 1.5U eq (C).  The asymmetric unit of (I), showing displacement ellipsoids at the 30% probability level.

Figure 2
Part of the one-dimensional chain structure of (I).  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.23 e Å −3 Δρ min = −0.22 e Å −3 Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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.