title: Crystal structure of catena-poly[[di-aqua-bis-(4-formyl-benzoato-κO (1))cobalt(II)]-μ-pyrazine-κ(2) N:N'].
abstract: In the title polymeric compound, [Co(C8H5O3)2(C4H4N2)(H2O)2] n , the Co(II) atom is located on a twofold rotation axis and has a slightly distorted octa-hedral coordination sphere. In the equatorial plane, it is coordinated by two carboxyl-ate O atoms of two symmetry-related monodentate formyl-benzoate anions and by two N atoms of two bridging pyrazine ligands. The latter are bis-ected by the twofold rotation axis. The axial positions are occupied by two O atoms of the coordinating water mol-ecules. In the formyl-benzoate anion, the carboxyl-ate group is twisted away from the attached benzene ring by 7.50 (8)°, while the benzene and pyrazine rings are oriented at a dihedral angle of 64.90 (4)°. The pyrazine ligands bridge the Co(II) cations, forming linear chains running along the b-axis direction. Strong intra-molecular O-H⋯O hydrogen bonds link the water mol-ecules to the carboxyl-ate O atoms. In the crystal, weak O-Hwater⋯Owater hydrogen bonds link adjacent chains into layers parallel to the bc plane. The layers are linked via C-Hpyrazine⋯Oform-yl hydrogen bonds, forming a three-dimensional network. There are also weak C-H⋯π inter-actions present.
authors.affiliation: Department of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey.
authors.forename: Gülçin Şefiye
authors.initials: GŞ
authors.lastname: Aşkın
authors.affiliation: Department of Chemistry, Kafkas University, 36100 Kars, Turkey.
authors.forename: Fatih
authors.initials: F
authors.lastname: Çelik
authors.affiliation: Aksaray University, Department of Physics, 68100, Aksaray, Turkey.
authors.forename: Nefise
authors.initials: N
authors.lastname: Dilek
authors.affiliation: Department of Chemistry, Kafkas University, 36100 Kars, Turkey.
authors.forename: Hacali
authors.initials: H
authors.lastname: Necefoğlu
authors.affiliation: Department of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey.
authors.forename: Tuncer
authors.initials: T
authors.lastname: Hökelek
keywords: benzoic acid derivatives; cobalt(II); crystal structure; one-dimensional coordination polymer; transition metal complexes