Synthesis and Structural Characterization of a Polyoxomolybdate HNa_7[Mo_(36)O_(112)(H_2O)_(16)]·47H_2O

A new polyoxomolybdate complex HNa7[Mo36O112(H2O)16]·47H2O 1 has been prepared in the beaker solution and characterized by single-crystal X-ray diffraction and elemental analyses. Crystal data: H127Mo36Na7O175, Mr = 6542.79, monoclinic, C2/c, a = 40.891(6), b = 17.900(3), c = 25.580(4) , β = 125.673(2)°, V = 15210(4) 3, Z = 4, Dc = 2.857 g/cm3, F(000) = 12464, μ = 3.013 mm-1, R = 0.0633 and wR = 0.1654 (I > 2σ(I)). With the bridging sodium cations, the [Mo36O112(H2O)16]8- units in compound 1 are linked to form a one-dimensional structure, on the basis of which a three-dimensional architecture is further constructed via other sodium cations and complicated hydrogen bonds.     

Synthesis, Structure, and Magnetic Properties of One Polyoxometalate (W/Mo) Compound: H_8K{[Ni(H_2O)_5]_2(H_2Mo_(1.80)W_(10.20)O_(42))}Cl_3·16H_2O

One new polyoxometalate compound connected via nickel/potassium cations, H8K{[Ni(H2O)5]2(H2Mo1.80W10.20O42)}Cl3·16H2O 1, was prepared and characterized by elemental analysis and IR spectroscopy. Single-crystal X-ray diffraction analysis results reveal that clusters of [Ni(H2O)5]2(H2Mo1.80W10.20O42)}6-in compound 1 are linked by potassium cations to form one- dimiensional chains, based on which a three-dimensional network is further constructed via the hydrogen bonds of O…O and O…Cl. Magnetic measurements show that compound 1 has para- magnetic properties. Crystal data: H62Cl3KMo1.80Ni2O68W10.20, Mr = 3461.33, monoclinic, space group C2/c, a = 18.9291(19), b = 16.6758(17), c = 19.1064(19), β = 106.6880(10)°, V = 5777.1(10)3, Z = 4, Dc = 3.980 g/cm3, F(000) = 6250, μ = 21.574 mm?1, R = 0.0579 and wR = 0.1623 (I > 2σ(I)).     

Structures of 1-（3,4-Dihydroxyphenyl）-2-（3,4-dimethoxyphenyl） ethanone and Its Hydrate Complex

The title compounds, C16H16O5 (I) and C16H16O5·H2O (II), were structurally characterized by single-crystal X-ray diffraction. Compound I crystallizes in monoclinic space group P21/c with a = 10.5574(10), b = 8.3576(9), c = 16.5528(16) , β = 91.762(3)°, Z = 4, R = 0.0524 and wR = 0.1084. The molecules are jointed into a chain by intermolecular O-H···O and C-H···O hydrogen bonds, which form layers parallel to (001). The chains run along the [110] and [110] directions alternatively layer by layer, and are assembled into a network by intermolecular O-H···O (carboxyl) hydrogen bonds. On the other hand, the hydrate complex (II) crystallizes in the triclinic space group P1 with a = 5.1451(2), b = 10.4583(4), c = 14.8267(5) , α = 70.900(2), β = 82.478(2), γ = 81.359(2)°, Z = 2, R = 0.0393 and wR = 0.0983. The molecules are linked into infinite two-dimensional ribbons by O-H···O (carbonyl) and solvent-bridged O-H···O hydrogen bonds.     

Synthesis and Crystal Structure of an Ionic Compound [Fe(CN)_6·(PhCH_2NC_9H_7)_4]·12H_2O

A novel ionic compound [Fe(CN)6(PhCH2NC9H7)4]·12H2O (C70H80FeN10O12, Mr = 1309.29) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. The compound crystallizes in triclinic, space group P1, with a = 10.968(7), b = 11.466(7), c = 14.077(8) , α = 87.014(7), β = 78.124(7), γ = 72.708(7)o, V = 1654.1(17) 3, Z = 1, Dc = 1.314 g·cm–3, F(000) = 692, μ = 0.298 mm–1, the final R = 0.0519 and wR = 0.1355. The building unit of the title compound consists of four (PhCH2N+C9H7) ions, one [Fe(CN)6]4– anion, and a dozen water molecules. According to the structural analysis, [Fe(CN)6]4– ions are linked together by O–H···O and O–H···N hydrogen bonds, while (PhCH2N+C9H7) and [Fe(CN)6]4– ions interact with each other by electrostatic force to form an ionic compound.     

Synthesis and Crystal Structure of an Ionic Compound [Fe(CN)_6(phCH_2NC_5H_5)3]·(H_2O)_4

A novel ionic compound [Fe(CN)6(phCH2NC5H5)3]·(H2O)4(Mr = 794.71) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. The compound crystallizes in monoclinic, space group P21/c with a = 10.837(2), b = 16.551(3), c = 23.402(5) , β = 97.531(4)o, V = 4161.0(15) A3, Z = 4, Dc = 1.269 g/cm3, F(000) = 1668, μ = 0.414 mm-1, R = 0.0479 and wR = 0.1232. The building unit of the title compound consists of three (phCH2N+C5H5) ions, one [Fe(CN)6]3- anion and four water molecules. According to the structural analysis, [Fe(CN)6]3- are linked together by O–H···N and O–H···O hydrogen bonds, but [Fe(CN)6]3- and [(phCH2N+C5H5)3] ions are bound by electrostatic force to form an ionic compound.     

Layered Lanthanum Complex with 3-Nitrophthalic Acid Assembled via Hydrogen Bonds-Synthesis, Structure and Characterization of [LaL(HL)(H_2O)_3]_2·2H_2O (H_2L=3-NO_2C_6H_3(CO_2H)_2)

A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2·2H2O (H2L = 3-nitro- phthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The complex crystallizes in triclinic system, space group P1 with a = 8.1549(16), b = 8.8856(18), c = 15.277(3) , α = 100.93(3), β = 90.81(3), γ = 104.56(3)°, V = 1049.8(4) 3, Z = 1, μ = 2.125 mm-1, Dc = 1.994 g/cm3, R = 0.0259 and wR = 0.0679. Two 3-nitrophthalates(2-) coordinate with the La3+ ions in a bridging mode, and two monohydrogen- 3-nitrophthates(1-) and three waters in terminal ways, respectively. Each La3+ ion is nine- coordinated to exhibit a distorted tricapped trigonal prism coordination polyhedron. Both the coordinated and crystal waters are involved in the inter- and intramolecular hydrogen bonds. The dinuclear units are linked into a 2D network structure in the ab plane via intermolecular hydrogen bonds along the axes a and b. Two crystal waters fill each rhombic pore of the network. The networks are further packed along the c axis forming a layered supramolecular structure through the C–H…O weak forces between the adjacent sheets. TGA analysis shows the complex undergoes the loss of waters of crystallization and coordination and the decomposition of ligands sequentially.     

Synthesis, Crystal Structure and Electrochemistry Properties of a (N,N'-Ethylene-bis(salicylaldiminato)) Nickel(II) Complex, [Ni_2(salen)_2]·NCS·NH_4

A new Ni(II) complex [Ni2(salen)2]·(NCS)·NH4 (salen = N,N’-bis(salicylidenea- mino)ethanato) has been prepared and structurally characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a = 16.8725(13), b = 19.0046(15), c = 20.0583(16) , Z = 8, V = 6431.8(9) 3, C33H32N6Ni2O4S1, Mr = 726.13, Dc = 1.500 g/cm3, F(000) = 3008, μ = 1.284 mm-1, the final R = 0.0394 and wR = 0.0767 for 4449 observed reflections with I > 2σ(I). The complex involves a N,N’-ethylene-bis(salicylaldiminato) Schiff base, an isothiocyanato anion and an ammonium cation. The nickle(II) ion adopts a distorted square coordination geometry with N2O2 set of Schiff base ligand. The complexes are linked into a dimmer via intermolecular hydrogen bonds and the [Ni(salen)] moieties are connected together to form a 2-D layer structure by intermolecular N–H…O hydrogen bonds and π-π stacking. Cyclic-voltammetry method was used to characterize electrochemically the complex.     

Synthesis and Crystal Structure of a New Iron Complex with Cyclic Water Hexamers [Fe(CDTA)(H_2O)]·[Fe(1,10-phen)_3]·10H_2O·2OH

The title complex [Fe(CDTA)(H2O)]·[Fe(1,10-phen)3]·10H2O·2OH (CDTA = transcyclohexane-1,2-diamine-N,N,N,N′-tetraacetate) has been prepared and characterized by single-crystal X-ray diffraction analysis. The crystal adopts space group P with a = 12.793(4), b = 14.104(5), c = 17.880(5), V = 2792.2(1)3, Dc = 1.459 g/cm3, C50H66Fe2N8O21, Mr = 1226.81, F(000) = 1284, μ = 0.604 mm-1, Z = 2, R = 0.1055 and wR = 0.2581 for 8675 observed reflections (I > 2σ(I)). X-ray crystallography analysis exhibits that the title compound consists of two crystallographically independent molecules [Fe(CDTA)(H2O)] and [Fe(1,10-phen)3], and they are connected through O-H···O hydrogen bonds and π···π stacking interactions forming a 3D supramolecular structure. Interestingly, there is a cyclic water hexamer with chair conformation in this complex.     

Synthesis, Crystal Structure and Photoluminescent Property of a Novel Silver(I) Compound {[Ag(bpp)]_2(Hphth)(NO_3)·(H_2O)_2}_n

Self-assembly of Ag(I) nitrate, 1,3-bis(4-pyridyl)propane (bpp) and phthalic acid monopotassium salt (KHphth) in CH3OH-H2O solution produced the title complex, {[Ag(bpp)]2(Hphth)(NO3)·(H2O)2}n, which was characterized by single-crystal X-ray diffraction, elemental analysis, IR spectrum, and photoluminescent spectrum. Single-crystal X-ray analysis revealed that the complex crystallizes in a monoclinic system, space group P21/c, with a = 15.4174(5), b = 8.6398(2), c = 25.2466(8) , β = 91.072(1)o, V = 3362.34(17) 3, Z = 4, C34H37N5O9Ag2, Mr = 875.43, Dc = 1.729 g/cm3, μ = 1.228 mm-1, F(000) = 1768, the final R = 0.0749 and wR = 0.1580 for 5754 reflections with I > 2σ(I). The Ag atom is coordinated by two N atoms from two bpp molecules in an approximately linear geometry. The Ag(I) ions are linked by the bpp molecules to form one-dimensional zigzag chains propagating along the c axis. The Hphth- and nitrate counter-ions are bridged by solvent water molecules through hydrogen bonds to generate a one-dimensional chain extending along the b axis. Electrostatic interactions between cations and anions, extensive hydrogen bonds and π-π interactions are responsible for the three-dimensional supramolecular structure. In the solid state, the compound exhibits blue photoluminescence with the maximum at 436 nm upon excitation at 344 nm.     

Synthesis and Crystal Structure of [Cu_2(DMF)(H_2O)(C_7H_4NO_4)_2(C_7H_3NO_4)]_2·3.5DMF

A new copper(II) complex [Cu2(DMF)(H2O)(C7H4NO4)2(C7H3NO4)]2·3.5DMF has been synthesized and its structure was determined by single-crystal X-ray diffraction.The crystal is of triclinic,space group P1 with a = 10.722(3),b = 18.170(4),c = 20.923(7),α = 105.297(9),β = 101.701(10),γ = 105.74(1)°,V = 3615(1) 3,Z = 2,C58.50H64.50Cu4N11.50O31.50,Mr = 1686.90,Dc = 1.550 g/cm3,μ = 1.255 mm-1,F(000) = 1728.00,T = 150(2) K,the final R = 0.0640 and wR = 0.173 for 11310 observed reflections with I > 2σ(I).In the crystal,each formular unit consists of two dinuclear copper(II) compounds,between which the O-H···O hydrogen bonds exist.Each CuII cation is six-coordinated in an octahedral geometry.The intermolecular hydrogen-bonding interaction leads to a 3-D framework of the title compound.     

Synthesis and Crystal Structure of an Unusual Dodecacoordinated Lanthanum Complex by Phenanthroline and Nitrate （phenH）_2[La（NO_3）_5（phen）]·CH_3OH

Lanthanum complex (phenH)2[La(NO3)5(phen)]·CH3OH (1, phen=phenanthroline) was synthesized and characterized by single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/c with a=20.3040(3), b=10.7091(1), c=19.0771(2), β=102.090(1)°, V=4056.07(8)3, Z=4, Dc=1.676 g/cm3, μ= 1.142 mm-1, F(000)=2056, the final R=0.0346 and wR=0.0793 for 9981 (Rint=0.0358) independent reflections. The mononuclear complex 1 consists of four parts: two phenH+ cations formed by the protonation of phen, one complex anion [La(NO3)5(phen)]2-, and one solvent methanol molecule. The complex anion contains one phen and five nitrate ligands which both chelate the center La(III) ion, adopting a distorted twelve-coordinated icosahedral geometry. The cations, anion and solvent molecule are linked together by hydrogen bonds. One of the protonated phenanthrolines (phenH+) acting as cation connects to the anion via N–H…O hydrogen bond directly, and the other one links to the anion through an intermediate solvent CH3OH via N–H…O and O–H…O hydrogen bonds. By the plentiful additional weak C–H…O intermolecular hydrogen bonds, the compound molecules construct a two-dimensional layer structure.     

Synthesis,Structure,Electrochemistry and Fluorescence Properties of a One-dimensional Coordination Polymer {[Cd[μ-(4,4′-dps)]_2(H_2O)_2]·(4-abs)_2(H_2O)_2}_n

A new cadmium(II) compound, {[Cd[μ-(4,4'-dps)]2(H2O)2]·(4-abs)2(H2O)2}n 1 (4,4'-dps = 4,4'-dipyridylsulfide, 4-abs = deprotonated 4-amino benzenesulfonic acid), has been synthesized and structurally characterized. It belongs to the orthorhombic system, space group Pbcn with a = 19.950(3), b = 10.6381(13), c = 18.055(2) , V = 3831.8(8) 3, Z = 4, C32H36CdN6O10S4, Mr = 905.31, F(000) = 1848, μ = 0.850 mm-1, Dc = 1.569 Mg/m3 , the final R = 0.0238 and wR = 0.0589 for 3080 observed reflections with I > 2σ(I). Complex 1 is a one-dimensional linear chain coordination polymer and the repeat unit is comprised of doubly charged cadmium complex cation, uncoordinated 4-aminobenzene sulfonate anions and water molecules. The cadmium(II) ion adopts a six-coordinate distorted octahedral geometry. Complex 1 is stabilized and linked into a three-dimensional layered structure through intermolecular O–H···O and N–H···O hydrogen bonds together with electrostatic force. The cyclic voltammograms and fluorescence spectrum of 1 were also measured. It shows one irreversible redox process and emits a very strong and sharp fluorescent band at about 341 nm.     

Investigation of Intermolecular C-H···Halogen Hydrogen Bonded Supramolecular Assemblies in Three Copper(Ⅰ) Complexes Formed by 3,3'-Dimethoxy-6,6'-dimethyl-2,2'-bipyridine Ligand

Three new crystalline compounds 1-3 were successfully obtained by the reactions of 3,3'-dimethoxy-6,6'-dimethyl-2,2'-bipyridine ligand(dmbp) with the corresponding Cu(Ⅰ) salts.Crystal data for 1:orthorhombic Pbca,a = 18.5858(12),b = 8.1821(5),c = 20.6066(13) ,V = 3133.7(3) 3,Z = 8,Dc = 1.843 g/cm3,F(000) = 1696,μ = 3.366 mm-1,the final R = 0.0223 and wR = 0.0542.Crystal data for 2:Orthorhombic Pbca,a = 18.7883(16),b = 8.3249(7),c = 19.0294(17) ,V = 2976.4(4) 3,Z = 8,Dc = 1.731 g/cm3,F(000) = 1552,μ = 4.154 mm-1,the final R = 0.0279 and wR = 0.0680.Crystal data for 3:monoclinic P21/c,a = 13.812(10),b = 9.910(7),c = 23.444(17) ,β = 104.3350(10)°,V = 3090(4) 3,Z = 4,Dc = 1.476 g/cm3,F(000) = 1408,μ = 1.588 mm-1,the final R = 0.0479 and wR = 0.1081.The results of X-ray crystallographic analysis revealed that C14H16ICuN2O2(1) and C14H16BrCuN2O2(2) are isostructural compounds with the dimers connected by C-H···halogen hydrogen bonds to generate a three-dimensional(3D) supramolecular network in 1 and a two-dimensional(2D) sheet structure in 2,respectively,while the mononuclear complex C28H32Cl2Cu2N4O4(3) is ionic.In 3,the [Cu(dmbp)2]+ cations and [ClCuCl]-anions are connected by C-H···Cl hydrogen bonds to form a one-dimensional(1D) chain along the a axis.Therefore,in the three complexes,the C-H···halogen hydrogen bonds dominate their crystal structures.Additionally,The UV luminescent properties of complexes 1-3 were investigated.     

SYNTHESIS AND STRUCTURE OF [4Ni(SALEN)·GGH] CLO_4· EtOH·H_2O (GG=Glycylglyciae)

The complex of [4Ni(salen)·GGH] CLO_4·EtOH·H_2O has been synthesized and studied by X-ray single crystal analysis. The results show that there are both intra-unit hydrogen bonds in the [4Ni(salen)·GGH]~+ and inter-unit hydrogen bonds between the two [4Ni(salen)·GGH]~+. Ni(salen) in the unit are still centrosymmetric dimers with planar structure. Imide N(10)—H(10) in the [GGH]~+ bonds with one phenolic oxygen 0(7) of Ni(salen) dimer in the same unit. Two H atoms of amino group N(9)— H [H(A), H(C)] in the glycylglycine perchlorate interact with phenolic oxygen [0(3), 0(5)] of [4Ni(salen)·GGH]~+ through two strong hydrogen bonds respectively.     

Synthesis and Crystal Structure of a New Supramolecular Compound Constructed from Flexible 1,1＇-（1,4-Butanediyl）bis（imidazole） and 1,2,4,5-Benzenetetracarboxylic Acid

A new bis(imidazolium) compound,[H2L(H2btec)2]·H4btec(1,L=1,1'-(butane-1,4-diyl)bis(imidazole),H4btec=1,2,4,5-benzenetetracarboxylatic acid),has been synthesized and structurally characterized by single-crystal X-ray diffraction.The title compound crystallizes in the monoclinic system,space group Pnma,with a=13.3908(11),b=13.9249(12),c=16.2166(14),V=2957.6(4)3,Z=4,Mr=698.55,Dc=1.569 mg/m3,F(000)=1448,μ(MoKα)=0.130 mm-1,the final R=0.0584 and wR=0.1538 for 4295 observed reflections with I2σ(I).The compound consists of one 1,1'-(butane-1,4-diyl)bis(imidazolium) cation,one neutral H4btec and one H2btec2-(Only two para carboxyl groups are deprotonated,and two protonated ones remain free) anion.A one-dimensional hydrogen bonding chain and a 2D hydrogen bonding network are formed via intermolecular N-H…O and O-H…O hydrogen bonds.These adjacent chains are further stacked through intermolecular π-π and hydrogen bonding interactions to form a 3D supramolecular network.     

Hydrothermal Synthesis and Crystal Structure of a New Polyoxovanadate:[Mn(en)_3]_2en_(0.5)[HV_8~ⅤV_8~ⅣO_(38)(Cl)]·4.5H_2O(en=Ethylenediamine)

A new compound has been synthesized under hydrothermal conditions and characterized by IR,elemental analysis,XPS and single-crystal X-ray diffraction analysis. The title compound [Mn(en)3]2en0.5[HV16O38(Cl)]·4.5H2O crystallizes in monoclinic,space group C2/c,with a=17.016(4),b=18.858(4),c=18.872(4),β=93.667(4)o,V=6043(2)3,Z=4,Dc=2.242 g/cm3,Mr=2040.12,F(000)=4020,μ=2.895 mm-1,Rint=0.0921,R=0.0649 and wR=0.1325. Single-crystal X-ray structure analysis indicates that the title compound consists of a polyanion [HV8VV8IVO38(Cl)]4-cage,two [Mn(en)3]22+ cations,four and a half lattice waters and a half ethylenediamine. In addition,intermolecular O-H···N,O-H···O,N-H···O and C-H···O hydrogen bonds link the molecules together to form a three-dimensional structure.     

Synthesis and Crystal Structure of a Co(Ⅱ) Complex with Taurine-5-methyl-2-hydroxyisophthalaldehyde Schiff Bases [Co(C_(13)H_(16)N_2O_7S_2)(H_2O)_3]_2·H_2O

The title complex CoL(H2O)32·H2O(C26H46N4O21S4Co2),where L = taurine-5-methyl-2-hydroxyisophthalaldehydes,has been synthesized and characterized by IR and X-ray diffraction analysis.The crystal of the complex belongs to the triclinic system,space group P1,with a = 11.197(4),b = 13.309(5),c = 14.486(5),α = 78.827(13),β = 70.547(11),γ = 81.058(13)°,Mr = 996.77,S = 1.08,V = 1987.2(13)3,Z = 2,Dc = 1.666 g/cm3,F(000)= 1032,μ = 1.131 mm?1,R = 0.0633 and wR = 0.1293.According to the structural analysis,the Co(Ⅱ)ion adopts a slightly distorted six-coordinated octahedral geometry.One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom.Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds,thus generating an infinite chain constructed by hydrogen bonds.     

Synthesis and Crystal Structure of [{Cd(hmbdc)(H_2O)_3}·2H_2O]_n

A novel coordination polymer [{Cd(hmbdc)(H2O)3}·2H2O]n (hmbdc = 5-hydroxy- isophthalic acid) has been synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c, with a = 9.599(3), b = 18.699(5), c = 7.557(2) , β = 108.198(4)°, V = 1288.6(6) 3, Z = 4, Mr = 382.60, Dc = 1.972 g/cm3, F(000) = 760, μ = 1.740, the final R = 0.0555 and wR = 0.0995 for 1732 observed reflections with I > 2σ(I). The structural analysis shows that the intermolecular hydrogen bonds and π-π interactions result in a three-dimensional supramolecular framework.     

Synthesis and Crystal Structure of [Zn(FcCOO)_2(2,2'-bipy)(H_2O)]_2·H_2O

A novel complex [Zn(FcCOO)2(2,2'-bipy)(H2O)]2·H2O (Fc = (η5-C5H5)Fe(η5-C5H4), 2,2'-bipy = 2,2'-bipyridine) has been synthesized and characterized by elemental analysis, IR and X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 6.8187(4), b = 21.7155(13), c = 19.7411(12) A, α = 90, β = 97.7420(10), γ = 90o, C64H58Fe4Zn2N4O11, Mr = 1413.28, V = 2896.4(3) A3, Dc = 1.620 g/cm3, Z = 2, F(000) = 1444, μ(MoKα) = 1.857 mm-1, R = 0.0523 and wR = 0.0982 for 3219 observed reflections (I > 2σ(I)). Structural analysis shows that the zinc atom is coordinated with three oxygen atoms from two ferrocenemonocarboxylates and one water molecule together with two nitrogen atoms from 2,2'-bipyridine, giving a distorted square-pyramidal coordination geometry. The complex molecules are linked to form an infinite one-dimensional chain by both intermolecular hydrogen bonds and π-π stacking interactions of the bipyridine rings.     

Synthesis, Crystal Structure and Luminescence Property of [Co(hmz)_2(H_2O)_4]·2H_2O

A new mononuclear Co(II) complex, [Co(hmz)2(H2O)4]·2H2O, has been synthesized by the reaction of Co(CH3COO)2·4H2O with 1-(4-hydroxyphenyl)-5-mercaptotetrazole (Hhmz). It crystallizes in the monoclinic system, space group P21/n with a = 13.502(5), b = 6.718(3), c = 13.972(6) , β = 117.532(4)o, V = 1123.9(8) 3, Z = 2, M r = 553.45, F(000) = 570, Dc = 1.635 g/cm3, μ = 1.008 mm–1, the final R = 0.0272 and wR = 0.0684 for 2194 observed reflections (I > 2σ(I)). The Co(II) is six-coordinated by two nitrogen atoms from two hmz–1 ligands and four water molecules, forming an octahedral geometry. The intermolecular hydrogen bonding and offset-panel π-π stacking interactions between the adjacent molecules extend the compound into a three- dimensional supramolecular framework. The title compound emits strong blue fluorescent light (λem(max) = 427 nm) at room temperature and is red-shifted compared with free ligand Hhmz (λem(max) = 342 nm).