title: Diaquabis(pyridine-2-carboxamide-kappa2N1,O2)nickel(II) disaccharinate tetrahydrate.
abstract: In the crystal structure of the title compound, [Ni(C6H6N2O)2(H2O)2](C7H4NO3S)2.4H2O or [Ni(pia)2(H2O)2](sac)2.4H2O (pia is picolinamide or pyridine-2-carboxamide, and sac is the saccharinate anion), the Ni2+ cation, located on a centre of symmetry, is coordinated by two symmetry-related aqua ligands together with a pair of symmetry-related bidentate pia molecules and exhibits a distorted octahedral environment. The unique unligated sac anion in the asymmetric unit resides on a general position and has a single negative charge. The coordinated water molecules link the sac ions to the metal complex via O-H...O hydrogen bonds. In addition, the sac ions are linked to the metal complex via intermolecular pi-pi interactions between the benzene ring of the sac ion and the pyridine ring of a pia ligand. Each uncoordinated water molecule is hydrogen bonded to sac moieties through O-H...O and O-H...N hydrogen bonds.
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Ondokuz Mayis University, 55139 Kurupelit Samsun, Turkey. hpasa@omu.edu.tr
authors.forename: Hümeyra
authors.initials: H
authors.lastname: Paşaoğlu
authors.forename: Fatma
authors.initials: F
authors.lastname: Tezcan
authors.forename: Okan Z
authors.initials: OZ
authors.lastname: Yeşilel
authors.forename: Halis
authors.initials: H
authors.lastname: Olmez
authors.forename: Hasan
authors.initials: H
authors.lastname: Içbudak
authors.forename: Orhan
authors.initials: O
authors.lastname: Büyükgüngör
mesh_terms: D018360:Crystallography, X-Ray; D004187:Disaccharides / Q000737:chemistry*; D005503:Food Additives / Q000737:chemistry; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D012439:Saccharin / Q000031:analogs & derivatives*; D013549:Sweetening Agents / Q000737:chemistry
chemical_list: D004187:Disaccharides; D005503:Food Additives; D009942:Organometallic Compounds; D013549:Sweetening Agents; C496374:diaquabis(pyridine-2-carboxamide-kappa2N1,O2)nickel(II) disaccharinate tetrahydrate; D009532:Nickel; D012439:Saccharin