title: Poly[diaquadi-μ-hydroxido-κ(4)O:O-dinitrato-κ(4)O:O'-bis-[3-(pyridin-4-yl-κN)-5-(pyridin-3-yl)-1,2,4-oxadiazole]dicopper(II)].
abstract: The title compound, [Cu(2)(NO(3))(2)(OH)(2)(C(12)H(8)N(4)O)(2)(H(2)O)(2)](n), consists of a neutral polymeric Cu(II) complex in which each Cu(II) atom has a distorted octa-hedral geometry defined by a pyridyl N atom from a 3-(pyridin-3-yl)-5-(pyridin-4-yl)-1,2,4-oxadiazole ligand and five O atoms from a water mol-ecule, two nitrates and two hydroxides. Two Cu(II) ions are bridged by two hydroxide anions resulting in a Cu(2)O(2) loop, located across an inversion center and connected by the nitrate anions into a broad two-dimensional polymeric structure parallel to (100). In the crystal, there are O-H⋯O hydrogen bonds between the coodinated water mol-ecule and the nitrate and hydroxide, and between the hydroxide and the nitrate. Inter-molecular π-π inter-actions are present between pyridine rings in adjacent two-dimensional structures, with a centroid-centroid distance of 3.582 (2) Å.
authors.affiliation: School of Chemistry and Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240,  People's Republic of China.
authors.forename: Longfei
authors.initials: L
authors.lastname: Wu
authors.forename: Linxia
authors.initials: L
authors.lastname: Huang
authors.forename: Mouhai
authors.initials: M
authors.lastname: Shu