Syntheses,crystal structures,and quantum chemistry calculation of two Ni(Ⅱ)coordination polymers

Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.

Synthesis, Structure and Luminescent Property of a 2D Cd(Ⅱ) Coordination Polymer Based on Mixed-ligands of 1,3-Bis(imidazol)propane and Pyridine-3,5-dicarboxylic Acid

A new Cd（Ⅱ） coordination polymer, namely, [Cd（1,3-bip）（3,5-pdc）]n （1,3-bip = 1,3-bis（imidazol）propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid） has been synthesized under hydrothermal conditions. Compound 1 was characterized by infrared spectrum, elemental analysis, powder X-ray diffraction （PXRD） and single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 1.40178（7）, b = 1.72502（12）, c = 1.41635（6） ran, β = 92.653（4）°, V = 3.4212（3） nm3, Z = 4, C16HIsCdNsO4, Mr = 453.73, Dc = 1.762 g/cm3, F（000） = 1808,μ = 1.310 mm1, R = 0.0899 and wR = 0.1945. In compound 1, each 3,5-pdc ligand links three Cd（lI） ions and each Cd（Ⅱ） attaches to bip ligands to form a complicated 2D double-layer structure. In addition, the thermal stability and luminescent property of 1 have been studied in the solid state at room temperature.

A New 2D Zinc(Ⅱ) Coordination Polymer Constructed by Imidazole-4,5-dicarboxylic Acid(H_3IDC) and 1,4-Bis(imidazol-1-ylmethyl)-benzene(bix)

A new 2D Zn（Ⅱ） coordination polymer [Zn（HIDC）（bix）0.5]n（1） was obtained by the hydrothermal reaction of ZnCl2,imidazole-4,5-dicarboxylic acid（H3IDC） and 1,4-bis（imidazol-1-ylmethyl）-benzene（bix） with a 2：2：1 mole ratio.X-ray diffraction crystal structural analysis reveals it crystallizes in monoclinic,space group P21/n with a = 12.125（3）,b = 10.541（3）,c = 12.484（3） ,β = 115.834（4）°,V = 1436.0（6） 3,Mr = 338.60,Z = 4,Dc = 1.566 Mg·m-3,F（000） = 684,μ（MoKα） = 1.730 mm-1,the final R = 0.0439 and wR = 0.0888 for 2101 observed reflections with I ≥ 2σ（I）.In 1,each zinc（Ⅱ） ion is five-coordinated with a slightly distorted trigonal bipy-ramidal coordination geometry,and each μ2-HIDC2-acts as a bridge to bond two neighboring Zn（Ⅱ） ions,leading to a 1D zigzag chain architecture.The adjacent zigzag chains are further linked by μ2-bix to form an infinite 2D network structure.The fluorescence spectrum of 1 exhibits intense emission at 466 nm when excited at 397 nm in solid state at room temperature.

Urothermal Synthesis and Crystal Structure of a Zn(Ⅱ) Coordination Polymer with a 3-D Supramolecular Structure

A new metal-organic coordination polymer [Zn（hfipbb）（e-urea）]n（1,H2hfipbb = 4,4＇-（hexafluoroisopropylidene）bis（benzoic acid）,e-urea = ethylene urea） has been urothermally synthesized and characterized by elemental analysis and single-crystal X-ray diffraction.The title complex crystallizes in monoclinic,space group P21/c with a = 13.302（4）,b = 10.981（3）,c = 13.804（4） ,β = 93.587（5）°,V = 2012.3（10） 3,C20H14N2O5F6Zn,Mr = 541.72,Z = 4,Dc = 0.447 g/cm3, = 0.328 mm-1,F（000） = 272,R = 0.0340 and wR = 0.1107 for 4528 observed reflections（I 〉2σ（I））.In the structure of compound 1,two Zn（Ⅱ） ions are bridged by two carboxylate groups from two hfipbb ligands to form a dinuclear unit,and each dinuclear Zn（Ⅱ） unit is linked with its two adjacent dinuclear units through four hfipbb ligands into an infinite one-dimensional double-chain.The interesting structural feature of compound 1 is that the one-D double-chains are self-interconnected into a three-D supramolecular structure through hydrogen bonds between the coordinated e-urea molecules and carboxylate oxygen atoms（N1 and O2,N2 and O4）.

Crystal Structure, Electrochemical and Fluorescent Properties of a New Copper(Ⅱ) Coordination Polymer with 2,3-Pyridinedi-carboxylic Acid

A new copper(Ⅱ)coordination polymer[Cu5(Hpt)5(H2O)2(2,3-PCA)2]n·12nH2O(1)has been successfully synthesized under hydrothermal conditions with copper hydroxide,3-(pyridin-2-yl)-1,2,4-triazole(Hpt)and 2,3-pyridinedi-carboxylic acid(2,3-PCA).The structure of the title compound was determined by X-ray diffraction analyses,elemental analyses and IR spectrum.The architecture of 1 consists of one-dimensional sandwich-like chains which are connected by extensive hydrogen bonding interactions.The solid-state photoluminescence displays an obvious emission band at 384 nm upon excitation at 340 nm.In addition,electrochemistry property has also been studied.

Synthesis,Crystal Structure,Thermal Stability,Luminescence and Magnetic Property of a New Mn^Ⅱ Coordination Polymer

One new coordination polymer, [Mn(Hbtc)(bpy)(HO)]1, was synthesized by the reaction of manganese(Ⅱ) salt under pH-controlled hydrothermal conditions with unsymmetrical polycarboxylic acid of 1,2,4-benzenetricarboxylic acid(Hbtc) and 2,2?-bipyridine(bpy). The structure of complex 1 was characterized by single-crystal X-ray diffraction, IR spectra, powder X-ray analysis, thermal gravimetric analysis(TGA), UV-Vis spectrometry, photoluminescence and magnetic susceptibility. Complex 1 is a one-dimensional(1D) polymeric single-chain structure. Photoluminescence property is quite similar to the bpy ligand. Magnetic susceptibility measurement indicates that 1 shows a weak ferromagnetic coupling between the Mn~Ⅱ ions.

Synthesis,Crystal Structure and Thermal Stability Properties of a Binuclear Copper(Ⅱ) Coordination Polymer {[Cu_2(4,4'-bipy)_2(o-ABA)_4(H_2O)_2][(H_2O)_2]}_n

One-dimensional chain copper（Ⅱ） coordination polymer has been synthesized and characterized in the solvent mixture of water and alcohol with o-acetamidobenzoic acid,4,4＇-bipyridine and copper perchlorate.It is of tetragonal,space group P41212 with a=1.57756（10）,b= 1.57756（10）,c=2.1438（3）nm,V=5.3352（8） nm^3,Dc=1.524 g/cm^3,Z=4,F（000）=2536,R= 0.0479 and wR=0.0979.The crystal structure shows two coordination modes.The copper（1） is coordinated with two nitrogen atoms of one 4,4＇-bipyridine molecule and two oxygen atoms from two o-acetamidobenzoic acid molecules,forming a distorted tetrahedral coordination geometry; the copper（2） is coordinated with two nitrogen atoms of one 4,4＇-bipyridine molecule,four oxygen atoms from two o-acetamidobenzoic acid molecules and two water molecules,generating a distorted octahedral coordination geometry.The result of TG analysis shows that the title complex is stable below 180.0 ℃.

Synthesis, Crystal Structure and Photoluminescence of a Zn(Ⅱ) Coordination Polymer Derived from 1,1'-Biphenyl-2,2',6,6'-tetracarboxylic Acid

A new polymeric znic（II） coordination polymer, [Zn2（bptc）·（H2O）4]n·nC H3 OH 1, was synthesized by the hydrothermal reaction of Zn（NO3）2·6H2O with 1,1＇-biphenyl-2,2＇,6,6＇-tetracarboxylic acid（H4bptc） and structurally characterized by single-crystal diffraction, IR and elemental analysis. The polymer crystallizes in the orthorhombic system, space group Pnna with a = 13.411（1）, b = 16.418（2）, c = 9.178（7）, V = 2025.2（3） 3, Z = 4, C17H14O13Zn2, Mr = 557.06, Dc = 1.827 g/cm3, F（000） = 1120, μ（MoK α） = 2.439 mm-1. The final R and wR are 0.0548 and 0.1691 for 1279 observed reflections with I 2（I）. In this compound, the bptc4- anion adopts monodentate bridging coordination modes connecting the zinc（II） ions to form a 1D chain structure, which furnishes a 2D supramolecular architecture through hydrogen bonding interactions formed by carboxylic oxygen atoms of bpdc, oxygen atoms of crystalline methanol and water molecules. Complex 1 displays an emissive maximum at 435 nm in the solid state at room temperature.

Construction of a Set of Cadmium(Ⅱ) Coordination Polymers with Atza and 2,2′-Bipy or 1,10-Phen Ligands (Atza=5-Aminotetrazole-1-acetato Anion)

Reactions of CdX2（X=NO3-, ClO4-） with Hatza （atza=5-aminotetrazole-1-acetato anion） and 2,2′-bipyridine （2,2′-bipy） or 1,10-phenanthroline （1,10-phen） in a methanol/aqueous solution produced a set of new Cd（Ⅱ） coordination polymers, {[Cd（atza）（H2O）（2,2′-bipy）]ClO4}n （1）, {[Cd（atza）（H2O）（1,10-phen）]ClO4 }n （2）, {[Cd（atza）（H2O）（2,2′-bipy）]NO3}n （3） and {[Cd（atza）2 （1,10-phen）]·0.5H2O}n （4）. Single-crystal X-ray diffraction analysis reveals that each Cd（Ⅱ） ion has a distorted octahedral coordination geometry in 1-4, and the Cd（Ⅱ） ion centers are connected through the tridentate atza bridging ligands to form a 2D layer （1-3） or ID chain （4） structure. The fluorescent properties of 2 and 4 are also discussed.

A Two-dimensional Anthracene-9,10-dicarboxylate Zinc(Ⅱ) Coordination Polymer Based on Binuclear [Zn_2Cl_2] Nodes: Synthesis, Characterization and Luminescent Properties

A two-dimensional（2D） 44 topological ZnⅡ coordination polymer {[Zn2Cl2（L）（4bpy）2]}∞（H2L = anthracene-9,10-dicarboxylic acid, 4bpy = 4,4ˊ-bipyridine） based on binuclear [Zn2Cl2] nodes has been synthesized and characterized by IR, elemental analysis, X-ray powder diffraction and single-crystal X-ray diffraction analysis. Moreover, the luminescent properties of the correspon- ding compound have been briefly investigated.

Synthesis,Crystal Structure and Photoluminescence Property of a Ni(Ⅱ) Coordination Polymer with One-dimensional Double-sinusoidal Structure

A new coordination polymer [Ni（3-bpo）（m-bdc）（C2H5OH） 2]n（1,3-bpo = 2,5-bis（3-pyridyl） -1,3,4-oxadiazole,m-H2bdc = 1,3-benzenedicarboxylic acid） was solvothermally synthesi-zed and characterized by IR,TGA and single-crystal X-ray diffraction. The title complex crystalli-zes in the orthorhombic system,space group Pnma with a = 7.786（3） ,b = 17.253（6） ,c = 18.478（6） ,V = 2481.9（14） A^3,Mr = 539.18,Dc = 1.443 g/cm^3,Z = 4,R = 0.0353 and wR = 0.0589. The m-bdc and 3-bpo bridge two Ni（Ⅱ） ions through two carboxylate groups and two pyridyl groups forming a 1D infinite double-sinusoidal chain along the c axis. The photoluminescence of 1 shows a large red shift compared to that of free ligands in the solid state.

Synthesis and Crystal Structure of a New Mn(Ⅱ) Coordination Polymer Based on Asymmetric Semi-rigid V-shaped Dicarboxylate

A novel manganese（Ⅱ） coordination polymer with 2-（4-carboxyphenoxy） benzoic acid （2,4＇-H2oba） and 1,10-phenanthroline （1,10-phen） has been prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction, IR and elemental analysis. Compound [Mn（2,4＇-oba）（1,10-phen）] is of monoclinic system, space group P21/n with a = 7.960（1）, b = 15.464（2）, c = 18.703（3）A, β = 99.976（2）°, V = 2267.5（6） A^3, Z = 4, Mr = 491.35, Dc = 1.439 g/cm^3, F（000） = 1004 and μ = 0.623 cm·1. The final R = 0.0419 and wR = 0.0978 for 3444 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that the oba2-ligands adopt a bis（chelating bidentate） mode to link two Mn（Ⅱ） centers to form an infinite 1D helical chain. Furthermore, a 3D supramolecular structure was formed by π-π stacking interactions and hydrogen bonds.

Structure and Magnetic Properties of a Bipyridine-bridged One-dimensional Ni(Ⅱ) Coordination Polymer

A polymer, [NiL（bipy）·2H2O]n（1, bipy = 4,4ˊ-bipyridine）, has been acquired by the reaction of Ni（OAc）2·4H2O with N,Nˊ-bis（2-hydroxyl-5-fluorobenzyl）-2-hydrxylpropane dii- mine in the presence of 4,4ˊ-bipyridine. X-ray crystallographic analysis shows that it is comprised of a mononuclear Ni（Ⅱ） complex [NiL] linked by 4,4ˊ-bipyridine. Its crystal crystallizes in the orthorhombic system, space group C2/c with a = 22.595（3）, b = 18.395（2）, c = 15.434（2） , V = 6155（1）3, Dc = 1.259 g/cm-3, Z = 8, Mr = 583.23, F（000） = 2416.0, μ（MoKa） = 0.681 mm-1, S = 1.049, R = 0.0512 and wR = 0.1108 for 6032 observed reflections（I 〉 2σ（I））. There are water hexamers in the complex. A weak overall ferromagnetic behavior has been evaluated by Curie-Weiss rule and by the formula of alternating ferro-ferromagnetic coupling in one-dimensional Ni（Ⅱ） chain, which gives g = 2.005（1） and J1 = 0.31（3） cm-1.

Synthesis, Structure and Magnetic Property of a New Three-dimensional Copper(Ⅱ) Coordination Polymer Constructed from 5-Tert-butyl Isophthalic Acid and N-donor Ligand

A new 3D copper（Ⅱ） coordination polymer, {[Cu_2（tbip）_2（1,3,5-tib）]×2H_2O}n（1, H_2 tbip = 5-tert-butyl isophthalic acid, 1,3,5-tib = 1,3,5-tris（1-imidazolyl）benzene）, has been synthesized by hydrothermal reaction of Cu（OAc）_2·4H_2O, H_2 tbip and 1,3,5-tib. It has been structurally characterized by element analysis, IR and magnetic measurement. X-ray single-crystal analysis was carried out for 1, which crystallizes in the triclinic system, space group P1 with a = 7.822（3）, b = 15.854（6）, c = 17.553（6） ？, a = 113.033（4）, β = 90.694（4）, g = 101.006（4）°, V = 1957.3（12） ？~3, Z = 1, D_c = 1.493 g/cm^3, M_r = 1759.70, F（000） = 908, R = 0.0721 and w R = 0.1978 with I 〉 2s（I）. The single-crystal X-ray diffraction studies reveal that compound 1 exhibits 2D [Cu（tbip）] layers which are further pillared by 1,3,5-tib ancillary ligand with terminal tridentate coordination mode to generate the final 3D structure. Magnetic susceptibility data for 1 have been measured in the range of 2~300 K. There are antiferromagnetic interactions between copper ions of the compound.

A One-dimensional Cd(Ⅱ)Coordination Polymer Constructed from 1,4-Benzene-dicarboxylic Acid and 3-(2,6-Di(pyrazin-2-yl)pyridin-4-yl)-1H-indole:Synthesis,Structure and Photoluminescence

A new coordination polymer {[Cd（C_（21）H_（14）N_6）（C_8H_4O_4）]·H_2O}_n（1） was synthesized by an elaborate design via the reaction of 3-（2,6-di（pyrazin-2-yl）pyridin-4-yl）-1H-indole（bppi）,1,4-benzene-dicarboxylic acid（H2bdc） and cadmium（Ⅱ） nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012（4）,b = 31.881（6）,c = 19.808（4） ？,V = 12638（4） ？~3,Z = 16,C_（29）H_（20）CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm^（-3）,μ = 0.735 mm^（-1）,F（000） = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections（I 〉 2σ（I））. The Cd（Ⅱ） centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd（Ⅱ） cations into a one-dimensional（1D） coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178（1） ？. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional（3D） structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ？~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm.

Synthesis and Crystal Structure of a Cu(Ⅱ) Coordination Polymer: [Cu(L)(1,10-phen)]_n

A new complex [Cu（L）（1,10-phen）]n （1, L = N-3-pyridine sulfonyl amino acid） has been synthesized and characterized by IR, elemental analysis and X-ray diffraction analysis, and its crystal belongs to monoclinic, space group P2Jc with a = 11.481 （2）, b = 1 8.094（4）, c = 8.5198（17） ]°, β= 102.26（3）°, V = 1729.5（6） ,/k3, Z = 4, Dc = 1.759 g/cm3, F（000） = 932, p = 1.422 mm-1, R = 0.0368 and wR = 0.0893. In 1, the Cu（ll） ion adopts a slightly distorted five-coordinated square pyramidal geometry. The L2- ligand adopts O of the carboxyl bridging adjacent Cu（Ⅱ）units to form an infinite chain structure along the c axis. Also, π-π stacking interactions between the adjacent chains expanded the 1-D structures into a 3-D supramolecular structure.

A Novel Three-dimensional Mn(Ⅱ) Coordination Polymer Constructed from Biphenyl-3,3',5,5'-tetracarboxylic Acid and Water

The title Mn（Ⅱ） coordination polymer,poly{[heptaaqua-（μ4-bi-phenyl-3,3？,5,5？-tetracarboxylate）-bimanganese（Ⅱ）] pentahydrate},[Mn_2（bpta）（H_2O）_7]_n·5n H_2O（I）,is crystallized from a mixture of biphenyl-3,3？,5,5？-tetracarboxylic acid（H_4bpta） and MnCl_2·4H_2O in waterethanol under room temperature. Its asymmetric unit consists of one and two halves of crystallographically independent Mn（Ⅱ） cations,one fully deprotonated H4 bpta ligand,seven coordinated water molecules and five solvent water as guest molecules. In I,each Mn（Ⅱ） atom is octahedrally coordinated by six oxygen atoms from bpta^（4-） anions and coordinated water molecules. In the Mn（Ⅱ） cations,one half Mn（Ⅱ） ion of them located at a 2-fold axis generating a trinuclear [Mn_3（H_2O）_2（RCOO）_2] linker by μ1,1-O（water） and μ1,3-O,O？（carboxylate） bridges and another half Mn（Ⅱ） ion with an inversion is a mononuclear linker. These neighbouring trinuclear and mononuclear Mn（Ⅱ） cations are linked together by biphenyl-3,3？,5,5？-tetracarboxylates to form a three-dimensional framework with a（42.84） topology of a（4,4）-connected net,in which the positions of the trinuclear [Mn_3（H_2O）_2（R-COO）_2] linker as a 4-connector linking four bpta^（4-） ligands in I reproduce an eagle-shaped arrangement. The polymeric structure exhibits a water channel with an accessible void of 797.1 ？~3,amounting to 15.7% of the total unit-cell volume. Each of the cavities in the network is occupied by solvent water molecules.

Syntheses, Crystal Structures, and Magnetic Properties of Mn(Ⅱ) and Co(Ⅱ) Coordination Polymers Constructed from Pyridine-tricarboxylate Ligand

Two coordination polymers, namely {[Mn（HL_1）（phen）]·4H_2O}_n（1） and [Co_2（HL_2）_2（H_2O）_2]_n（2） have been constructed hydrothermally using H_3L_1 and H_3L_2（H_3L_1 = 2-（5-carboxypyridin-2-yl）terephthalic acid, H_3L_2 = 2-（4-carboxypyridin-3-yl）terephthalic acid）, phen, MnCl_2×4H_2O and CoCl_2×6H_2O. The products were isolated as stable crystalline solids and were characterized by IR spectroscopy, elemental, thermogravimetric（TGA）, powder（PXRD） and single-crystal X-ray diffraction analyses. Compound 1 features a 3D framework structure, which was topologically classified as a trinodal 4,6,6-connected net with the unique topology defined by the point symbol of（3^（10）.5.6~4）4（3^（10）.6.7~4）2（5.6~2.8~2.9）. Compound 2 possesses a 2D metal-organic layer, which was topologically classified as a binodal 4,4-connected layer defined by the point symbol of（4~3.6~2.8）. The layers are further extended into a 3D supramolecular framework via hydrogen bonds. The magnetic properties for both compounds were also investigated, indicating antiferromagnetic interactions between the adjacent metal ions.

Synthesis, Structure and Magnetic Property of One Ni~Ⅱ Based Coordination Polymer

One new coordination polymer, [Ni（m-bix）（m-BDC）]（1, m-bix = 1,3-bis（imidazol-1-ylmethyl）benzene, m-BDC = 1,3-benzenedicarboxylic acids）, has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, TGA and X-ray single-crystal diffraction. The green block crystal of complex 1（C22H18N4Ni O4） belongs to monoclinic system, space group P21/c with a = 10.0418（3）, b = 23.8651（6）, c = 8.7872（2） A, β = 112.333（3）°, V = 1947.88（9）A3, Z = 4, Dc = 1.572 g/cm^3, Mr = 461.11, F（000） = 952, R = 0.0335 and w R = 0.0683 for 2827 observed reflections（I 〉 2σ（I））. Complex 1 exhibits a novel 6-connected 3D sxd type topological framework. The magnetic characterization of complex 1 shows antiferromagnetic coupling exchange.

Two Cobalt(Ⅱ)Coordination Polymers Based on Tetrazylphosphonate and Tetrazylphosphonic Acid Ligands

Two cobalt coordination polymers with the same 2D structure have been hydrothermally synthesized based on two bifunctional ligands with tetrazole and phosphonate（phosphonic acid） groups,namely,diethyl 4-（2H-1,2,3,4-tetrazol-5-yl） benzylphosphonate（C_2H_5-L1） and 4-（2H-1,2,3,4-tetrazol-5-yl）benzylphosphonic acid（H_2L2）. The structures of the two complexes are characterized by elemental analysis,IR,TGA and X-ray single-crystal/powder diffraction. The pink block crystals of complex [Co（L1）（H_2O）]·H_2O（1） belong to the monoclinic system,space group C2/m with a = 20.8390（11）,b = 7.2695（3）,c = 10.0156（6） A,β = 109.773（7）°,V = 1427.80（13） A^3,Z = 4,D_c = 1.680 mg/cm^-3,M_r = 361.16,F（000） = 740,R = 0.0316 and wR = 0.0826 for 1702 observed reflections（I 〉 2σ（I））. The purple block crystals of complex [Co（L2）（H_2O）]·2H_2O（2） also belong to the monoclinic system,space group C2/c with a = 25.5382（16）,b = 7.3844（3）,c = 15.1925（11） A,β = 124.238（9）°,V = 2368.6（2） A^3,Z = 8,D_c = 1.969 mg/cm^-3,M_r = 351.12,F（000） = 1432,R = 0.0475,wR = 0.1617 for 2088 observed reflections（I 〉 2σ（I））. Both the nitrogen atoms of tetrazole group and oxygen atoms of phosphonate（phosphonic acid） groups in the ligands coordinated with the metal cobalt. The magnetic property of complex 1 is also investigated.