title: Aqua-bis(2-methyl-4-oxopyrido[1,2-a]pyrimidin-9-olato)zinc(II) monohydrate.
abstract: The crystal structure of the title compound, [Zn(C(9)H(7)N(2)O(2))(2)(H(2)O)]·H(2)O, involves discrete mononuclear complex mol-ecules. The special positions on the rotation twofold axis are occupied by Zn(II) and O atoms of the coordinated and uncoordinated water mol-ecules. The coordination around the Zn(II) atom can be described as transitional from trigonal-bipyramidal to square-pyramidal. The two chelating 2-methyl-4-oxopyrido[1,2-a]pyrimidin-9-olate ligands and the coordin-ated water mol-ecule form the Zn coordination. O-H⋯O hydrogen bonds between the coordinated water mol-ecule and the ligand and between the uncoordinated water mol-ecule and the ligand dominate the crystal packing.
authors.affiliation: Ordered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Wei
authors.forename: Zhong-Shu
authors.initials: ZS
authors.lastname: Li
authors.forename: Huai-Hong
authors.initials: HH
authors.lastname: Zhang
authors.forename: Yi-Hong
authors.initials: YH
authors.lastname: Wang