title: Tetra-aqua-bis(2-methyl-benzimidazolium-1,3-diacetato-κO)zinc(II) tetra-hydrate.
abstract: The asymmetric unit of the title compound, [Zn(C(12)H(11)N(2)O(4))(2)(H(2)O)(4)]·4H(2)O, contains one-half of the complex mol-ecule and two uncoordin-ated water mol-ecules. The four water O atoms in the equatorial plane around the Zn(II) centre ( symmetry) form a distorted square-planar arrangement, while the distorted octa-hedral coordination geometry is completed by the O atoms of the zwitterionic 2-methyl-benzimidazolium-1,3-diacetate ligands in the axial positions. The benzimidazole ring system is planar, with a maximum deviation of 0.041 (3) Å. Intra-molecular O-H⋯O hydrogen bonding results in the formation of a non-planar six-membered ring. In the crystal structure, strong intra- and inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. π-π contacts between benzimidazole rings [centroid-centroid distance = 3.899 (1) Å] may further stabilize the structure.
authors.affiliation: School of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin 541004, People's Republic of China.
authors.forename: Heng-Chi
authors.initials: HC
authors.lastname: Lian
authors.forename: Qing-Ling
authors.initials: QL
authors.lastname: Ni
authors.forename: Xuan-Feng
authors.initials: XF
authors.lastname: Jiang
authors.forename: Zhong-Min
authors.initials: ZM
authors.lastname: Cen
authors.forename: Jia-Huang
authors.initials: JH
authors.lastname: Lin