One novel adduct based on aminopyridinium and biphenyl-2,4′-dicarboxylate, C5H7N2＋·C14H9O4-, has been synthesized and characterized by X-ray structural study. The compound crystallizes in trigonal, space group P32 with a = 9.2886（16）, b = 9.2886（16）, c = 16.746（6） , γ = 120°, V = 1251.2（5） 3, C19H16N2O4, Mr = 336.34, Dc = 1.339 g/cm3, μ（MoKα） = 0.095 mm-1, F（000） = 528, Z = 3, the final R = 0.0438 and wR = 0.1119 for 3097 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Its electronic structure was calculated at the RHF/6-31G（d） level and a detailed analysis of intermolecular interactions was used by Hirshfeld surface and fingerprint plot. Intermolecular N-H…O hydrogen bonds link two components generating R22（8） rings which are linked into three one-dimensional chains in the [100], [010] and [110] directions, and these chains are finally arranged into a three-dimensional framework by hydrogen bonds. Investigation of intermolecular interactions via Hirshfeld surface analysis reveals that the close contacts are mainly associated with the classical hydrogen bonding interactions. The HOMO-LUMO energy gap of the compound indicates a higher kinetic stability.
A cocrystal based on 1,3-di（4-pyridyl）propane and 3-（（4′-carboxybenzyl）oxy）benzoic acid,C13H14N2·C15H12O5,has been synthesized and characterized by single-crystal X-ray diffraction.The compound crystallizes in monoclinic,space group P21 /c with a = 11.639（4）,b = 9.808（3）,c = 20.854（6）,β = 91.242（7）°,V = 2380.0（13）3,C28H26N2O5,Mr = 470.51,Dc = 1.313 g/cm3,μ（MoKα） = 0.091 mm-1,F（000） = 992,Z = 4,the final R = 0.0677 and wR = 0.1477 for 4175 observed reflections（I 2σ（I））.Intermolecular N H···O hydrogen bonds link two kinds of components into a one-dimensional chain in [10-1] direction and adjacent chains are further arranged into a two-dimensional network by π···π and C H···π interactions.Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analysis reveals that the close contacts are mainly focused on weak interactions.The theoretical investigations with HF/6-31G（d） method were performed,and its stability,frontier molecular orbital composition and Mulliken charge distribution were also discussed.
An organic-inorganic hybrid based on a-Keggin-typed [BWI2040]5- anionic cluster, [Co（BIIM）3]2H[BWx2040]＇7H20 （BIIM = 2,2＂-biimidazole）, was hydrothermally synthesized and structurally characterized by thermogravimetric analysis, IR and UV spectra. The title compound crystallizes in monoclinic, space group P21/n with a = 12.3490（10）, b = 33.270（3）, c = 18.9660（16） A, β = 105.9950（10）°, V= 7490.5（11） A3, C36HsoBCo2N24047W12, Mr = 3905.80, Dc = 3.45 l g/cm3, μ（MoKa） = 18.886 rnm-1, F（000） = 6972, Z = 4, S = 1.004, the final R = 0.0404 and wR = 0.0914 for 14683 observed reflections （1 〉 2tr（/））. The compound consists of two isolated [Co（BIIM）3]2＋ cations and one [BW12040]5 anion, in which each Co2＋ ion is coordinated by six N atoms from three BIIM ligands displaying a regular CoN6 octahedron. These components are finally linked together via N-H...O（polyoxometalate and wate） hydrogen bonds into a two-dimensional framework. Full investigation of the intermolecular interactions by Hirshfeld surface and fingerprint plots clearly indicates that there are rare W--Oterminal···πimidazole ring interactions which cooperate with the classical N-H···O hydrogen bonds to stabilize the structural packing.
A sandwich-type tungstophosphate, （1,3-H2dap）8-14[Co4（H2O）2（α-B-PWgO34）2]2·5H20 （1,3-dap = 1,3-diaminopropane）, was hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR and UV spectroscopy. The title compound crystallizes in triclinic, space group P1 with a = 13.691（3）, b = 17.744（4）, c = 20.620（5） A, a =113.466（5）, β = 91.184（5）, Y = 104.223（5）°, V = 4414.3（17）A^3, C24H96Co8N16O145P4W36, Mr = 10143.09, Dc = 3.816 g/cm^3,μ（MoKa） = 24.210 mm^-1, F（000） = 4452, Z = 1, the final R = 0.0694 and wR = 0.1519 for 9910 observed reflections （I 〉 2σ（I））. The compound consists of two sets of tetra-transition metal-substituted sandwich frameworks, [Co4（H2O）2（α-B-PW9O34）2]^10- having an inversion centre. Two lacunary α-B-[PW9O34]^9- Keggin units are linked by a rhomb-like Co4O14（H2O）2 cluster, in which the Co^2＋ ions are coordinated by one water molecule. Isolatedly protonated 1,3-H2dap^2＋ units act as counter-ions to interact with the [Co4（H2O）2（α-B-PWgO34）2]^10- heteropolyanions via hydrogen bonds, resulting in a three-dimensional framework.
The title coordination polymer including two crystallographically independent Co2＋ ions is hydrothermally synthesized, in which the Co（1） 2＋ ion is four-coordinated by two carboxylate oxygen atoms from two different 5-（benzoic acid-4-yldiazenyl）isophthalate （byip3-） anions and two nitrogen atoms from two distinct 1,4-bis（imidazol-1-ylmethyl） benzene （bix） ligands displaying a tetrahedral geometry. The Co（2） 2＋ ion is six-coordinated by two water molecules at the apical positions, and two carboxylate oxygen atoms and two nitrogen atoms at the equatorial positions, affording a slightly distorted octahedron. Two Co（1）2＋ and two Co（2）2＋ ions are linked together by four byip3- anions forming a 44-membered motif and these motifs are further arranged into a three-dimensional framework through bix ligands along the a axis with a larger channel （ca. 22.70×11.01）. Each individual network interpenetrates with the other identical network in a parallel fashion to generate a 2-fold interpenetrating array with the {62.84}{63}2{64.82}2 topology.
