catena-Poly[[diaqua­nickel(II)]-bis­(μ-2-{[5-(pyridin-4-yl)-1,3,4-oxadiazol-2-yl]sulfan­yl}acetato)]

In the title compound, [Ni(C(9)H(6)N(3)O(3)S)(2)(H(2)O)(2)](n), the Ni(II) atom, located on an inversion center, is ligated in an octa­hedral geometry by two carboxyl­ate O atoms from two 2-{[5-(pyridin-4-yl)-1,3,4-oxadiazol-2-yl]sulfan­yl}acetate (L) ligands and two O atoms from water mol­ecules in the equatorial plane, and two pyridine N atoms from other two L ligands at the apical sites. Two L ligands bridge pairs of metal atoms in an anti­parallel manner, forming centrosymmetric dinuclear quasi-recta­ngular units which are linked into infinite double-stranded chains parallel to [100]. O—H⋯O hydrogen bonds between the coordinating water mol­ecules and the carboxyl­ate groups of the L ligand as well as interchain S⋯N inter­actions [2.726 (2)–3.363 (2) Å] lead to the formation of a layer structure parallel to (001).