title: Assembly of a cubic nanocage Co8L12 and a hydrogen-bonded 3D NbO net based on the [(HCO3)2]2- synthon and water.
abstract: Two new complexes [Co(H2O)6 Co8(L1)12]X6 x n H2O (X = NO3(-), n = 12 (1); X = HCO3-, n = 24, (2); HL1 = 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol) have been synthesized and characterized by single-crystal X-ray diffraction. A [Co(H2O)6](2+) ion is encapsuled in the central cavity of the cubelike nanocage [Co(H2O)6 Co8(L1)12](6+) cation, assembled by eight cobalt ions at the corners and twelve bis-bidentate ligands L1 as the edges, via the formation of 12-fold strong hydrogen bonds between the six coordinated water molecules and the oxygen atoms of twelve L1 as a guest. Complex 1 crystallizes in a centrosymmetric space group P1, while 2 is in a very high symmetric space group Im3. In 2, a planar [(HCO3)2](2-) dimer motif R2(2)(8) synthon plus six lattice water molecules constitute a planar supramolecular synthon R8(8)(20), which acts as a four connector, generating a 3D hydrogen-bonded NbO net with cubelike host cavities of approximately 20 A diameter. Interestingly, the cubelike nanocage [Co(H2O)6 Co8(L1)12](6+) cations fill in the cavities as templates. The magnetic properties of 1 have also been studied in the temperature range of 2-300 K, and its magnetic susceptibility obeys the Curie-Weiss law, showing antiferromagnetic coupling.
authors.affiliation: MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
authors.forename: Man-Li
authors.initials: ML
authors.lastname: Cao
authors.forename: Hong-Guo
authors.initials: HG
authors.lastname: Hao
authors.forename: Wei-Xiong
authors.initials: WX
authors.lastname: Zhang
authors.forename: Bao-Hui
authors.initials: BH
authors.lastname: Ye
mesh_terms: D001639:Bicarbonates / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019281:Dimerization; D006860:Hydrogen Bonding; D008024:Ligands; D008280:Magnetics; D049329:Nanostructures / Q000737:chemistry*; D009556:Niobium / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D014227:Triazines / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D001639:Bicarbonates; D008024:Ligands; D009942:Organometallic Compounds; D010087:Oxides; D014227:Triazines; D009556:Niobium; D014867:Water; D003035:Cobalt