Synthesis and Crystal Structure of a Two-dimensional Cadmium Complex Based on Terephthalate and 1-Methyl-2,2'-bibenzimidazole

The title complex, Cd(MeHbibzim)(1,4-bdc)n (1, MeHbibzim = 1-methyl-2,2'- bibenzimidazole, 1,4-bdc = terephthalate), was synthesized with hydrothermal reactions. The compound crystallizes in monoclinic, space group C2/c with a = 9.822(4), b = 18.510(7), c = 22.372(9), β = 98.359(6)°, C23H16CdN4O4 , Mr = 524.81, V = 4024(3)3 , Z = 8, Dc = 1.733 g/cm3 , μ(MoKα) = 1.126 mm-1 , F(000) = 2096, the final R = 0.0597 and wR = 0.1374 for 3906 observed reflections (Ⅰ > 2σ(Ⅰ)). X-ray diffraction analysis reveals that the Cd atom is coordinated by two nitrogen atoms from the chelating MeHbibzim and three carboxyl oxygen atoms from three terephthalate ligands, thus forming a distorted square pyramidal coordination sphere, CdN2O3. Every two Cd atoms are linked together via two carboxyl groups into a dinuclear unit with Cd···Cd separation of 3.806(4). The dinuclear building units are linked by terephthalate ligands into two-dimensional layers, which are further aggregated into a 3D framework via hydrogen bonding interactions.     

Hydrothermal Synthesis and Crystal Structure of a 2D Zinc（Ⅱ） Coordination Polymer with 5-Hydroxynicotinic Acid

The title compound,[Zn(5-hydroxynicotinate) 2 2H 2 O] n,has been synthesized by reacting zinc sulfate vitriol with 5-hydroxynicotinic acid under hydrothermal conditions,and its structure was determined by X-ray crystallography with the following data:monoclinic,space group C2/c,C 12 H 12 N 2 O 8 Zn,M r=377.61,a=10.223(3),b=10.319(3),c=13.613(4),β=105.922(6)°,Z=4,V=1380.9(8)3,F(000)=768,D c=1.816 g/cm 3,μ(MoKα)=1.826 mm-1,the final R=0.0401 and wR=0.1380 for 1157 observed reflections (I > 2σ(I)).In the structure of the title compound,the Zn II ion located in an inversion center lies in a distorted tetrahedral environment at a N 2 O 2 coordination mode,and the 5-hydroxynicotinic acid ligand links symmetry-related Zn II ions at a μ 2-N,O bridging way forming a two-dimensional covalent structure.In the crystal,solvent water molecules form intermolecular O-H O hydrogen bonds and pyridine rings of adjacent layers form π-π stacking (3.346),which connect adjacent two-dimensional sheets into a three-dimensional supramolecular network.     

One Pillared Layered Zn(Ⅱ) Coordination Compound Based on 2,6-Naphthalenedicarboxylic Acid: Synthesis,Structure and Luminescent Property

One new pillared layered zinc hydroxide {Zn_4(OH)_6(ndc)·2(H_2 O)}_n,(H_2 ndc =2,6-na-phthalenedicarboxylic acid) has been achieved under hydrothermal conditions by using2,6-na-phthalenedicarboxylic acid, 2,4-diami-6-phenyl-1,3,5-triazine as well as Zn(OAc)_2·2 H_2 O,and structurally characterized by X-ray single-crystal diffraction, IR spectra, elemental analysis,powder X-ray diffraction(PXRD) and thermogravimetric analysis(TGA). The X-ray single-crystal diffraction proves that the title compound is in monoclinic system, space group P2_1/c with a =16.362(8), b = 9.324(5), c = 5.364(3) ?, β = 99.081(9)°, V = 808.1(7) ?~3, D_c = 2.522 g/cm~3, M_r =613.73, Z = 2, F(000) = 608, μ = 5.935 mm~(-1), GOOF = 1.050, R = 0.0469 and wR(Ⅰ 2σ(Ⅰ)) =0.1291. In the title compound, the tetrahedral and octahedral zinc atoms are connected by μ_3-OH groups to form zinc hydroxide inorganic layers extending parallel to the bc-plane. The adjacent layers are pillared by the connection of Zn2 atoms with ndc~(2-)ligands to construct a three-dimensional(3D) structure; meanwhile, the interactions of five hydrogen bonds make the 3D network structure more stable. Furthermore, the title compound exhibits luminescent property at solid state.     

A Novel Two-dimensional Lead(Ⅱ) Coordination Polymer Based on Dinuclear Lead(Ⅱ) Unit Containing(5-Chloro-quinolin-8-yloxy) Acetate

A novel two-dimensional lead(II) coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand(5-chloro-quinolin-8-yloxy)acetic acid(HL) with PbCl2, and its structure was characterized by IR, elemental analysis, TG-DTA and single-crystal X-ray diffraction analysis. The crystal is of monoclinic system, space group P21/c with a = 16.7603(7), b = 8.6907(4), c = 8.4745(3), β = 101.1110(11)°, C11H7Cl2NO3 Pb, Mr = 479.27, V = 1211.25(9)3, Z = 4, Dc = 2.628 g/cm3, F(000) = 880, μ = 14.367 mm-1, R = 0.0173 and wR = 0.0508. The asymmetric unit contains one lead(II) cation, one(5-chloro-quinolin-8-yloxy)acetate(L) ligand and a chloride ion. The PbII center is hepta-coordinated in a distorted pentagonal bipyramidal geometry. The coordination sphere of the Pb atom is completed by two oxygen atoms and one nitrogen atom of the same L ligand, two bridging chloride ions and two bridging oxygen atoms of two adjacent L ligands. Two PbII centers are linked by the two L ligands to form a C2-symmetric dimer unit with a planar [Pb2O2] ring. Each dimer unit acts as a secondary building unit(SBU) and links adjacent four dimer units by the chloride atoms and oxygen atoms of carboxylate groups of L, forming a two-dimensional array. Such two-dimensional layers are packed through intermolecular C–H···Cl hydrogen bonds into a three-dimensional supramolecular structure. When the dimer unit is viewed as a 4-connected node, 1 is simplified as a 4-nodal 2-D network with square lattices of the diagonal lengths to be 6.079(1). The fluorescence emission peak of complex 1 appears near 407 nm.     

一个新的噻二唑衍生物H2ADTZ与锰的二维聚合物的合成与晶体结构(英)

A new 1,3,4 thiadiazole-derivative ligand 2,5-(s-acetic acid) dimercapto-1,3,4 thiadiazole (H₂ADTZ) and its one-dimensional manganese polymer Mn(ADTZ)·4H₂O had been synthesized and structurally characterized by X-ray single crystal diffraction in this paper. The Mn(Ⅱ) ion is coordinated with a distorted octahedron by two oxygen atoms from neighboring two deprotonated ligands ADTZ^2- and other four oxygen atoms from four coordinated water molecules. The structural feature of the title compound is the formation of one-dimensional manganese chains polymer through the bridging of dioxygen O-O units. In the solid state structure of the complex, one-dimensional manganese chains are joined together by the weak intermolecular hydrogen bonds and vander Waals interactions forming a two-dimensional supramolecular compound. Furthermore, the UV spectra and electro-chemical properties of the title compound were also investigated. CCDC: 260532.     

Synthesis and Crystal Structure of a New [Mn_2Ni_2] Cubane Complex

A new Mn2Ni2 cubane complex has been synthesized and characterized by single-crystal X-ray diffraction,FT IR spectra and elemental analysis.The title compound [MnIII2NiII2(hmp)4(N3)4(O2CR)2](hmp-is the anion of 2-pyridinemethanol and O2CR-is α-na-phthaleneacetate)crystallizes in the monoclinic system,space group P21/c with a = 10.519(5),b = 22.109(10),c = 23.235(9),β = 106.096(17)o,C48H42Mn2N16Ni2O8,Mr = 1198.28,V = 5192(4)3,Dc = 1.533 g/cm3,F(000)= 2448,μ = 1.258 cm1,Z = 4,the final R = 0.0875 and wR = 0.2020 for 3398 reflections with I > 2σ(I).X-ray diffraction analysis reveals that each Mn(III)center is octahedrally coordinated by two nitrogen atoms of azide anions and three oxygen atoms from three 2-pyridinemethanol anion ligands together with one oxygen atom from naphthaleneacetate.Each Ni(II)is octahedrally coordinated by two nitrogen atoms of 2-pyridinemethanol anion ligands as well as three oxygen atoms from three 2-pyridinemethanol anion ligands and one oxygen atom from naphthaleneacetate.     

Ionothermal Synthesis and Characterization of a Three-dimensional Anionic Zinc-5-sulfoisophthalate Framework Charge-balanced with the 1-Ethyl-3-methylimidazolium

The ionothermal reaction of Zn(NO_3)_2·6H_2O with 5-sulfoisophthalic acid monosodium salt(NaH_2SIP) and 1,2,4-triazole in 1-ethyl-3-methylimidazolium tetrafluoroborate(EMIM-BF_4) ionic liquid has afforded the compound {(EMIM)[Zn(SIP)]}_n(1).The Zn(Ⅱ) ions are linked by the carboxylate groups of SIP~(3-) ligands to give a two-dimensional layered structure featuring the centrosymmetric dinuclear Zn_2(μ_2-COO)_2 units.The adjacent two-dimensional layers are further linked by the Zn-0 bonds between the Zn(Ⅱ) ions and the sulfonate O atoms to generate a three-dimensional anionic[Zn(SIP)]_n~(n-) framework featuring one-dimensional open channels propagating along the a axis.The imidazolium cations[EMIM]~+ derived from ionic liquid act as extraframework charge-balancing species for the anionic[Zn(SIP)]_n~(n-) framework and occupy the void space of the one-dimensional open channels.The rich ionic environments of the ionic liquid may be particularly helpful in the formation of the ionic compound 1.The roles of the ionic liquid in ionothermal synthesis and crystallization of the compound are briefly discussed.Furthermore,compound 1 displays a photoluminescent emission at 490 nm upon excitation at 406 nm.     

Structure and Properties of a New Rare-earth Borate LiSrY_2（BO_3）_3

The structure of LiSrY2(BO3)3 has been solved by single-crystal X-ray diffraction analysis at 298 and 113 K on different diffractometers.It crystallizes in trigonal with space group P-3m1(No.164).The cell parameters at room temperature are as follows:a = 10.3345(9),c = 6.4049(11) ,V = 592.41(13) 3,Z = 3,Mr = 448.81,F(000) = 618,μ = 21.327 mm-1 and Dc = 3.774 g/cm3.The crystal structure consists of gear-like [BY6O33] groups which are linked together by corner-sharing to form a two-dimensional layer parallel to the ab plane.These layers are connected one after another by sharing oxygen atoms with B(2) atoms along the c direction to construct a three-dimensional framework.Li and Sr atoms just occupy the cavities formed by oxygen atoms.In addition,the vibrational spectroscopy of LiSrY2(BO3)3 and photoluminescence properties of the Eu3+ doped LiSrY2(BO3)3 were also studied.     

Structure of BaGd2（MoO4）4 Crystal

The title compound belongs to monoclinic,space group C2/c with a=5.2694(1),b=12.6659(4),c=19.4108(2) ,β=91.504(2)°,V=1295.06(5) 3,Z=4 and Dc=5.599 g/cm3. The structure of BaGd2(MoO4)4 contains a MoO4 tetrahedron,a distorted GdO8 polyhedron,and Ba2+ ions in a tenfold coordination. The GdO8 polyhedra are linked together through edge-sharing to give a two-dimensional Gd layer. The MoO4 tetrahedra connected to the Gd atoms are capped up and down the Gd layer through common oxygen apices,thus forming a new Gd-Mo layer. Finally,the Gd-Mo layers are held together through bridging BaO10 polyhedra to form a three-dimensional framework. Since the Ba-μ3-O bond has a large average distance of 2.888 ,this structural characteristic will result in a cleavage along the (001) plane.     

Hydrothermal Synthesis,Crystal Structure and Magnetic Properties of a Novel Cobalt Complex Based on Biphenyl-3,3＇,4,4＇-tetracarboxylate

A novel cobalt complex,[Co2(bptc)(bix)1.5](1,H4bptc=3,3',4,4'-biphenyltetra-carboxylic acid,bix = 1,4-bis(imidazol-1-ylmethyl)benzene),has been hydrothermally prepared and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal is of triclinic system,space group P1 with a=10.770(7),b=12.245(8),c=13.514(9),α=102.829(8),β=107.734(8),γ=98.833(9)°,C37H27N6O8Co2,Mr=801.51,V=1607.5(18)3,Dc=1.656g/cm3,F(000)=818,μ=1.100mm-1,Z=2,the final R = 0.0694 and wR = 0.1543 for 3034 observed reflections(I2σ(I)).In the title complex,the two Co(Ⅱ) ions are in different coordination environments with distorted octahedral and trigonal bipyramidal geometries,respectively.The Co atoms are linked together through hexadentate bptc ligands,giving rise to 2D layers which are bridged by the bix ligands into a 3-D supramolecular network.Magnetic susceptibilities of 1 reveal weak antiferromagnetic exchange interactions between the adjacent Co(Ⅱ) ions.     

Synthesis and Crystal Structure of a Novel 2-Fold Interpenetrating Three-dimensional Coordination Polymer,{[Co_3（byip）_2（bix）_3（H_2O）_2]·H_2O}_n

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.     

Synthesis and Crystal Structure of a New Complex [Cu（C_（14）H_9O_3）_2（C_5H_5N）_2（C_2H_5OH）_2]

The title compound of Cu(C14H9O3)2(C5H5N)2(C2H5OH)2(1) was synthesized via the hy- drothermal reaction of CuCl2·2H2O and 9-hydroxy-fluorene-9-carboxylic acid(HHF) with pyridine, and characterized by elemental analysis and infrared spectra. The crystal belongs to triclinic, space group P1 with a = 8.8302(12), b = 10.1625(14), c = 12.2708(17), α = 86.207(2), β = 69.562(2), γ = 64.932(2)o, V = 930.3(2) 3, Z = 1, Mr = 764.30, Dc = 1.364 g/cm3, F(000) = 399, S = 1.059 and μ(MoKα) = 0.644 mm-1. The final R = 0.0459 and wR = 0.1274 for 3414 observed reflections with I 2σ(I). The copper atom is six-coordinated by two oxygen atoms from two different 9-hydroxy-fluorene-9-carboxylate ligands, two pyridine nitrogen atoms and two ethanol oxygen atoms, forming a distorted octahedral coordination geometry. The extensive O–H···O hydrogen bonding connects the molecules to form a one-dimensional chain structure. Between adjacent one-dimensional chains, a two-dimensional layered structure was formed by fluorene ring π-π packing interaction. Between the layers, a three-dimensional structure was formed through the π-π packing interaction of the pyridine ring. Moreover, the thermal stability and photoluminescent property of the complex has been investigated.     

A Novel 3D Supramolecular Framework of Poly[(5-(oxidediphenylphosphino)isophthalate)zinc(Ⅱ)]: Syntheses and Structure

A novel metal-organic framework, namely [Zn(C20H13O5P)]n(1), has been hydrothermally synthesized through the reaction of 5-(oxidediphenylphosphino)isophthalic acid(H2L) with Zn(Ⅱ) salt. The title compound crystallizes in monoclinic, space group P21/c with a = 11.0966(10), b = 14.5651(14), c = 14.7311(15), β = 130.022(6)o, C20H13O5 PZn, Mr = 429.64, V = 1823.3(3) 3, Dc = 1.565 g/cm3, F(000) = 872, μ = 1.463 mm-1, S = 1.054 and Z = 4. The final R = 0.0270 and wR = 0.0739 for 2769 observed reflections with I 2σ(I). In the title complex, the Zn2(CO2)2 binuclear clusters are linked by L2- ligands to result in a pillared layer structure in the bc plane, which is a(4,4)-net composed of helical chains with opposite chirality by sharing Zn2(CO2)2 units. Adjacent layers are further associated together through Zn–O bonds involving the metal center and the oxygen atom of P=O group to achieve a 3D architecture, in which one-dimensional quadrangled channel displays the interweaving of two pairs of coaxial double-helical chains with opposite chirality. The luminescence property and thermogravimetric analysis of the title complex were investigated.     

Synthesis and Crystal Structure of 2,3,4,6-tetra-O-Acetyl-1-{4-chloro-3-[1-（4-ethoxyphenyl）-1-methylethyl]phenyl}-1-deoxy-β-D-glucopyranose

The title compound was synthesized and its crystal structure was determined by single-crystal X-ray diffraction.The crystal is of monoclinic system(C31H37ClO10,Mr = 605.06),space group P21 with a = 11.882(5),b = 10.106(5),c = 13.816(6),V = 1545.9(12)3,Z = 2,Dc = 1.300 g/cm3,F(000) = 640,μ = 0.179 mm-1,the final R = 0.0430 and wR = 0.0595 for 4960 observed reflections(I > 2σ(I)).The title compound was confirmed to be a β-anomer by single-crystal X-ray diffraction and 1H NMR.The proximal benzene ring is nearly orthogonal to the glucopyranoside ring,and the two benzene rings are also almost orthogonal to each other.Four non-classical intermolecular hydrogen bonds observed in the crystal lattice help to stabilize the crystal.     

Synthesis and Crystal Structure of a Coordination Polymer [Zn（p-pdoa）（bbp）]n with a One-dimensional Helical Chain

The coordination polymer [Zn（p-pdoa）4（bbp）]n 1 （p-pdoa = p-phenylenedioxydiacetate dianion and bbp = 2,6-bis（benzimidazol-2-yl）pyridine） has been synthesized by hydrothermal method and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The title complex crystallizes in the triclinic system, space group P1^- with a = 7.8383（2）, b = 12.6610（4）, c = 13.1792（5）A, a = 84.433（2）,β = 74.2980（1）, γ = 87.4290（1）°, V = 1252.93（7）A^3, Z = 2, Dc = 1.593 g/cm^3,/z = 1.038 mm^-1, F（000） = 616, the final R = 0.0361 and wR = 0.1139. The Zn（Ⅱ） atom assumes a distorted trigonal bipyramidal geometry, involving two carboxyl O atoms from two different p-pdoa ligands and three N atoms from the bbp ligand. The Zn（Ⅱ） atom is alternately interlinked by p-pdoa ligands in a bismonodentate mode into a helical chain with a long pitch of 12.661 A and the adjacent Zn…Zn distance of 11.056 and 12.245 A. There exists a 2D supramolecular framework linked by π-π stacking （3.312 A） between adjacent benzimidazoles of bbp ligands and intermolecular hydrogen-bonding interactions between the uncoordinated carboxylate oxygen atoms （O（2）, 0（5）） and the uncoordinated imidazolyl N atoms （N…O distances 2.706 and 2.786 A）. There also exist two interlayer π-π stacking interactions of 3.299 A between adjacent central pyridines of bbp ligand and 3.176 A between the phenyl groups of p-pdoa ligand. Such π-π stacking interactions extend the two-dimensional layers into a 3D supramolecular network.     

Crystal Structure and Properties of a Copper(Ⅱ) Complex Containing p-Toluenesulfonate and Imidazole Ligands

A novel supramolecular mixed ligand complex of formula [Cu(PTS)2(Him)2(H2O)2] (C20H26CuN4O8S2,PTS=p-toluenesulfonate,Him=imidazole) has been synthesized in aqueous solution and characterized by elemental analysis,IR and single-crystal X-ray diffraction.The compound crystallizes in the monoclinic system,space group P21/n,Z=2,a=5.650(2),b=14.671(3),c=14.638(3),β=100.10(3)°,V=1194.60(4)3,Dc=1.607 g/cm3,μ(MoKα)=1.143 mm-1,F(000)=598,R=0.0615 and wR=0.1503 for 1752 observed reflections with I 2σ(I).The copper(II) ion in the complex adopts a slightly distorted octahedral coordination geometry and is six-coordinated with N2O4 donor set consisting of two nitrogen atoms and four oxygen atoms provided by the ligands of two imidazole molecules,two water molecules and two p-toluenesulfonate ions.The sulfonate group of the PTS ligand remains weak-coordinated and forms a number of hydrogen bonds with water molecules and imidazole ligands.X-ray structural analysis reveals that the coordination molecules are connected to form a 3-D supramolecular framework by electrostatic interaction,weak van der Waals forces,hydrogen bonding and π-π interaction.The thermal behaviour of the title complex was investigated by using DSC and TG-DTG techniques.     

Syntheses and Crystal Structures of （PySe）2 and Bi2（PySe）6（HPySe=2-Pyridineselenol N-Oxide）

The title compounds(PySe)2 1(HPySe=2-pyridineselenol N-oxide,(PySe)2= bis(2-pyridine-N-oxide) diselenide) and Bi2(PySe)6 2 were prepared by the reaction of 2-bromine-N-oxide with NaHSe and Bi(NO3)3·5H2O with HPySe,and the crystal structure of 2 was studied.Compound 2 crystallizes in the monoclinic space group P21/n with a=9.840(2),b=10.204(2),c=18.395(2),β=102.926(2)°,V=1800.0(5)3,Dc=2.2687 g/cm3,Z=2,the final R=0.0319 and wR=0.0646.The Bi atoms are coordinated by four selenium and four oxygen atoms from four PySe ligands to form a slightly distorted four-column geometry.     

Synthesis and Structural Characterization of Co( Ⅱ ) Coordination Polymer [Co(μ-phth)(imi)2]n

A new cobalt( Ⅱ ) complex [Co(μ-phth)(imi)2]n (phth = o-phthalato, imi = imidazole)has been synthesized by the reaction of CoCl2 with disodium o-phthalate and imidazole. The crystal structure of the compound has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic system, space group Pn with a = 8.405(1), b = 9.995(1), c = 9.996(2) (A),β= 104.479(2),V= 813.0(2) (A)3, Dc= 1.467 g/cm3, C14H12N4O4Co, Mr= 359.21, F(000) = 366,μ = 1.079 mm-1, Z = 2, R = 0.0483 and wR = 0.1209 for 1583 observed reflections (Ⅰ＞ 2σ(Ⅰ)). In the title complex, the Co(Ⅱ) ions are bridged by o-phthalate ligands in a bidentate mode, producing a zigzag infinite chain structure. Each four-coordinated cobalt( Ⅱ ) center was coordinated by two oxygen atoms and two nitrogen atoms to give a distorted tetrahedral geometry. The chains are linked by hydrogen bonds between oxygen atoms belonging to carboxylate groups and hydrogen atoms of imidazole molecules, forming an unusual two-dimensional coordination polymer.     

THE SYNTHESIS AND CRYSTAL STRUCTURE OF A NOVEL TETRANUCLEAR COPPER (Ⅰ) CLUSTER COMPLEX, Cu_4(α-C_(10)H_7CSS_2)_4·1/2CS_2

The title compound has been synthesized by the reaction of sodium α-dithionaphthoatewith CuCl_2 in an alkaline aqueous solution or by the reaction of α-dithionaphthoic acid withCuCl_2 in an organic solvent, The crude product was recrystallized in a mixture of CS_2 andC_2H_5OH. The crystals obtained are red and stable in air. The structure of the title compound is determined by a single-crystal X-ray diffractionanalysis. The crystal belongs to monoclinic space group C_(2h)~5- P(2_1/a) with unit cell parameters:a= 16.453(3)A, b=12.651(4)A, c=23.182(7)A, β=100.5(2)°, V=4744.6A~3,Z=4. Thestructure was refined to R=0.06 for 4707 reflections. In the molecule, Cu_4 cluster has a distorted tetrahedral configuration. Surrounding thistetrahydron are four α-perthionaphthoate ligands, coordinated to copper through the sulfuratoms. One of the sulfur atoms in each ligand forms sulfur bridge with copper atoms,while the other is coordinated to only one copper. The three Cu--S bonds formed by thethree sulfur atoms with a given copper atom are approximately coplanar. Each group--C--S_2 with Cu atom on a vertex of the tetetrahedron forms a five-member ring. Thesefive-member rings are also approximately cooplanar. The molecule possesses an approachingS_4 point symmetry. The mechanism for the formation of the title compound involves a redox reaction.which is discussed in this paper.     

Solvothermal Synthesis, Crystal Structure and Luminescent Property of a Dy（Ⅲ） Coordination Polymer Constructed by 1,2,4,5-Benzenetetracarboxylic Acid

A three-dimensional coordination polymer {[Dy(H2btec)2/4(btec)3/6(H2O)]·2H2O} n has been synthesized through the reaction of DyCl3·6H2O and 1,2,4,5-benzenetetracarboxylic acid by solvothermal technique, and the crystal structure was determined by X-ray diffraction. The Dy(Ⅲ) coordination polymer crystallizes in monoclinic, space group P21/n with a=10.7063(1), b=7.1491(1), c=17.1197(3), α=90, β=97.10, γ=90°, V=1300.31(3)3 , C10H9DyO11 , Dc=2.389g/cm3 , Z=4, F(000)=892, the final R=0.0165 and wR=0.0448 for I > 2σ(I). The title coordination polymer possesses a three-dimensional framework consisting of nine-coordinate Dy(Ⅲ) centers and two kinds of coordination modes for the 1,2,4,5-benzenetetracarboxylic acid ligands. Every btec4- ligand (deprotonated four protons from 1,2,4,5-benzenetetracarboxylic acid) in the title coordination polymer can clamp three Dy atoms like forceps, which could make the Dy atoms closer in the area of metal-metal interaction. The 3-D framework of the coordination polymer has many channels occupied by the free guest water molecules, and the hydrogen bonds between the coordinated carboxylic groups and guest water molecules could stabilize the crystal structure of the title coordination polymer. In addition, the luminescence properties were also studied.