Synthesis,Crystal Structure and Photoluminescence Property of Ag(I) with N,N-dimethyl-4-(pyridine-4-yldiazenyl)aniline

A 2D plane coordination compound [Ag_2(Dpya)_2.(NO_3)_2]n was synthesized and characterized by FT-IR,elemental analysis and TG analysis.The red crystal was obtained via solvent diffusion method at room temperature and is slightly soluble in organic solvents.Its structure was determined by single-crystal X-ray diffraction analysis.It crystallizes in monoclinic,space group P1 with a = 10.7995(13),b = 7.4748(8),c = 18.364(2) ?,β = 98.916(4)o,V = 1464.5(3) ?~3,Z = 2,C_(26)H_(28)Ag_2N_(10)O_6,M_r = 792.32,Dc = 1.302 Mg/m~3,F(000) = 792,μ(Mo Ka) = 1.356 mm~(-1),R = 0.0575 and w R = 0.0826.The compound [Ag_2(Dpya)_2.(NO_3)_2]_n is a two-dimensional structure and there are two kinds of coordination configurations about the Ag atoms in the compound.The Ag(1) center is tetrahedrally coordinated with two O atoms of NO_3~-and two N atoms from the ligand Dpya.Meanwhile,the Ag(2) is five-coordinated by five O atoms from three NO_3~-anions.The Ag centers(Ag(1) and Ag(2)) connect to themselves as well as with each other by the bridging NO_3~-anions.And the coordination compound shows photoluminescence with an emission peak at 530 nm(λex = 450 nm) as the ligand Dpya.     

A STUDY ON CONFIGURATION-ACTIVITY RELATIONSHIP OF DIAMMINEDICHLOROPLATINUM (Ⅱ) BY THE PSEUDOPOTENTIAL VALENCE ELECTRON-ONLY ab initio CALCULATION METHOD

We investigated the cis- and trans-isomers of Pt(NH_3)_2Cl_2 and [Pt(NH_3)_2]~(2+) using a quantum chemical non-empirical calculation method, the pseudopotcntial valence electron only ah initio method. The electronic structure and electrostatic potential counter maps were in turn determined through the wave functions so obtained. There was a sharp difference between the dipole moments of the cis- and trans-isomers. The electrostatic counter maps of the isomers also had remarkably different features. Based on the interaction between the platinum (Ⅱ) coordination compound and the base pairs of nucleic acid, the difference in antitumour activity of the isomeric compounds was discussed, It is pointed out that the key factor for antitumour activity is that the platinum (Ⅱ) coordination compound must be mutually complementary with the target acceptor in both configuration and bonding activity. This mutualcomplementary requirement includes a bonding ability of the platinum complex with two negative centers i     

Structures and Photoluminescent Properties of 3D Ho(Ⅲ) and Y(Ⅲ) Complexes with 2,4,6-Pyridinetricarboxylate

Two 3D rare earth coordination polymers {[Ho(ptc)(H_2O)_(2.5)]·0.5 H_2O}n(1) and {[Y2(ptc)2(H_2O)_5]·H_2O}n(2)(H_3ptc = 2,4,6-pyridinetricarboxylic acid) have been synthesized with Ho(Ⅲ) or Y(Ⅲ) chloride and H_3ptc by hydrothermal method. The X-ray structure analyses display the two complexes are isomorphic and crystallize in monoclinic crystal system with P21/n space group for 1 and P21/c space group for 2. Ho(Ⅲ) and Y(Ⅲ) both show two different coordination modes. One is nine-coordinated and forms a distorted tricapped trigonal prism and the other is eight-coordinated to get a distorted bicapped trigonal prism. The ptc3-also shows two different coordination modes by connecting four or three rare earth ions. The photoluminescent properties of 2 show that it can emit blue fluorescence at 440 nm with excitation at 335 nm. The fluorescence lifetime of 2 is 1.64 μs and the absolute fluorescence quantum yield is 10.2%.     

Reactions of magnesium formate on supports

Thermal decomposition of supported magnesium formate has been studied by gas chro-matography.The reaction paths of decomposition of supported magnesium formate depend on thenature of the supports.For Mg(HCO_2)_2/HZSM-5,the zeolite behaves as a dehydration catalyst togive CO and H_2O at lower temperatures;when the zeolite is modified by phosphorus,the methanationreaction will be partly restrained.In the case of Mg(HCO_2)_2/AC,strong adsorption of CO_2 leadsto the formation of the shoulder peak of CO_2 at higher temperatures,however,CH_4 disappears aftermodified by phosphorus.For Mg(HCO_2)_2/Al_2O_3,the dehydrogenation of HCO_2~- takes place on thesurface of Al_2O_3.The decomposition of Mg(HCO_2)_2 on SiO_2 in hydrogen yields two peaks of COand only one appears after modified by phosphorus.When Mg(HCO_2)_2 decomposes on MgO,the firstpeak of CO_2 arises from the reaction of surface Mg~(2+) with HCO_2~- from dissociated Mg(HCO_2)_2.     

Three Complexes Based on Synthetic-condition Strategy Involving a Universal Mixed-ligand System

Three coordination polymers([Zn(H_2biim)_2(H_2O)_2]_2·2(HO-BDC)·x(H_2O)(1)[Cd(H_2biim)_2(H_2O)_2]_2·2(HO-BDC)·x(H_2O)(2) and [Co(HO-BDC)(bbi)]n(3)) are obtained by using synthetic-condition strategy in the mixed-ligand system 5-hydroxyisophthalic acid(OH-BDC)together with bisimidazole ligands(2,2?-biimidazole(H2 biim) and 1,1?-(1,4-butanediyl)bis(imidazole)(bbi)). The structure determination reveals that complexes 1 and 2 are zero-dimensional(0 D) structures, and complex 3 is a dinuclear two-dimensional(2D) layer structure. They are all 3D supramolecular networks. The comparisons of the synthetic-condition effects and structure differences among 1 ～3 and our previous work complexes 4([Co_2(HO-BDC)_2(bbi)_2]·H_2O) and 5([Zn(HO-BDC)(bbi)]) have been discussed in detail. Furthermore, the luminescent properties and thermal stabilities of compounds 1～3 in the solid state have been studied.     

Mixed-solvothermal Synthesis,Crystal Structure and Luminescence of a New Dinuclear Yttrium(Ⅲ) Coordination Polymer with 1-D Wave-like Infinite Chains

A new dinuclear Y~(3+) coordination polymer{[Y_2(H_2O)_2(C_(14)H_8O_4)_3(C_(12)H_8N_2)_2]·3 H_2O}_n (1, C_(14)H_8 O_4 = 2,2?-biphenyldicarboxylate, phen = 1,10-phenanthroline), has been obtained by means of a mixed-solvothermal method using ethylene glycol and water as solvent. The compound was characterized by elemental analysis, energy-dispersive X-ray spectroscopy(EDS), IR spectrum and single-crystal X-ray diffraction. The results reveal that 1 belongs to monoclinic system, space group C2/c with a = 24.249(3), b = 12.069(48), c = 22.7304(08) ?, β = 113.480(7)°, Z = 4, V = 6102(2) ?~3, Dc = 1.462 g·cm~(-3), F(000) = 2728, μ = 1.968 mm~(-1), the final R = 0.0673, w R = 0.1508 and S = 1.085. Its structure can be regarded as a 1-D coordination polymer constructed by Y~(3+) cations, 2,2?-biphenyldicarboxylate, 1,10-phenanthroline and water molecules. The compound not only contains two kinds of organic ligands, but also exhibits interesting wave-like infinite chains and 18-MR windows with the diameter of 4.070(7)? × 5.326(9)?. The structure is further stabilized by means of O–H···O hydrogen bonds and π-π stacking interactions. Furthermore, the luminescent properties(including emission spectrum, CIE chromaticity coordinate and decay curve) of 1 were also investigated in the solid-state at room temperature.     

One Novel Mn(Ⅱ) Complex with 1-Substituted-1H-1,2,3-triazole-4-carboxylic Acid:Crystal Structure,Fluorescence and Hirshfeld Surface Analysis

The crystal structure of one novel Mn(II) complex, [Mn(pmta)_3]_2[Mn(H_2O)_6]·4H_2O(1), is reported(Hpmta = 5-methyl-1-phenyl-1H-1,2,3-triazole-4-carboxylic acid). In the title compound, the asymmetric unit consists of a [Mn(pmta_)3]ˉ anion, half [Mn(H_2O)_6]~(2+) counter cation and two lattice H_2O molecules, and the intra- and intermolecular hydrogen bonds connect the complex into a supramolecular structure. The liquid-state fluorescence spectra of complex 1 have been determined. Hirshfeld surface analysis was also studied. The main intermolecular interactions in the complex are O···H and H···H contacts.     

Two 2D uranyl coordination complexes showing effective photocatalytic degradation of Rhodamine B and mechanism study

Two new hydrostable two-dimensional(2 D) uranyl coordination complexes [(UO_2)_5(μ_3-O)_2(nbca)_2].7 H_2O(1) and [(UO_2)_3(nbca)_2(H_2O)_3]·2 H_2O(2)(H_3 nbca=5-nitro-1,2,3-benzenetricarboxylic acid) were hydrothermal synthesized.Single-crystal structural refinements reveal that both of the two complexes were formed by the packing of 2D uranyl coordination sheets via the hydrogen bonds.The nbca ligand coordinating to the uranyl polyhedron centers constructed the 2D sheets.There are UO_8 hexagonal bipyramids and UO_7 pentagonal bipyramids in 1 while only U07 pentagonal bipyramids in 2.Photocatalytic degradation of rhodamine B(RhB) in aqueous solution was studied.Complex 2 possesses better performance than 1 with 96.2 % of the RhB was degraded in only 60 min.Mechanism studies reveal that the dissolved oxygens are essential to the RhB degradation.The photocurrent density of 2 is more stable than that of 1,which indicating the stronger ability to separate photoexcited electrons and hole pairs of 2.     

SYNTHESIS AND CRYSTAL STRUCTURES OF {Pr[(C_2H_5O)_2POO]_3}_n

The synthesis, characterization and crystal structure of rare earth coordination complex of {Pr[(C_2H_5O)_2POO]_3}_n has been studied. It is triclinic with space group P1 in a unit cell of dimensions a=11.788(5), b=12.536(3), c=10.262(2.) , α=112.21(2), β=93.01(3), γ=109.94(3)°; V=1290.9(8)~3, Z=2. As shown in Fig. 1, each Pr atom is connected with other two Pr atoms through three "O-P-O" bridging groups to form a long chain polymer. The coordination number of Pr is six. The six coordinated O atoms form an octahedron. The average bond distance of Pr-O is 2.333 A. The complex has been also studied by infrared spectroscopy and thermal analyses.     

SYNTHFSIS AND CHARACTERIZATION OF LANTHANIDE COMPARTMENTATL COMPLEXES, ln_2 [h_2 (BAA)_2 en]_2·pH_2O

A series of new complexes of formula Ln_2[H_2(BAA)_2en]_3nH_2 Otwhere Ln- La,Pr, Eu, Cd, Dy, Er, Yb, n-1-4) have been prepared by the reaccLon of lanthanideions with acycllc compartmental ligand X, N'-bis(benzoylacetylacetone)ethylenediamine(H_4(BAA)_2 en) in methanol. IR and UV spectra, as well as TC DAT analysis prove thatthe ligand and the Lanthanide ions have coordinated. The coordination number is 12and the complexes may be of double sandwiched structure.     

Two Metal Ion-controlled Zn(Ⅱ)/Cd(Ⅱ) Coordination Polymers Based on 1,3,5-Benzenetricarboxylic Acid

Two new coordination polymers {[Zn(Hbtc)(bpyb)]·H_2O}n(1) and {[Cd(Hbtc)-(bpyb)_(1.5)]·0.5 bpyb}_n(2)(H_3btc = 1,3,5-benzenetricarboxylic acid, bpyb = 1,4-bis(4-pyridyl)benzene) have been synthesized under hydrothermal conditions. The two compounds were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Compound 1 displays a 2-fold interpenetrating 3D supramolecular architecture through O–H···N/O hydrogen bonds and π-π stacking interactions. Compound 2 exhibits a 2D→3D polycatenated structure, which is further stabilized by O–H···N hydrogen bonds. The results indicate that the metal ion has significant effects on the formation and structure of the resulted coordination polymers. Furthermore, thermal stability and photoluminescent properties of 1 and 2 are also discussed in detail.     

A Novel 3-D Zn(Ⅱ) Coordination Polymer for Inhibiting the Human Osteosarcoma Cells Growth

A new three-dimensional Zn(II) coordination polymer, namely [Zn_4(bpydb)_3(tz)2(H_2O)_2]n(1), has been synthesized by the self-assembly reactions of Zn(NO_3)_2·6H_2O, bpydb H_2, Htz and DMF. Single-crystal X-ray structural analysis reveals that compound 1 features a three-dimensional framework structure and is the first example of Zn-containing coordination polymers based on two kinds of ligands bpydb H_2 and Htz. It crystallizes in triclinic, space group P1 with a = 14.9953(12), b = 17.5335(17), c = 20.2381(11) ?, α = 115.225(7), β = 92.329(5), γ = 105.606(8)o, V = 4561.9(7) ?3, Z = 2, F(000) = 1644, Dc = 1.177 Mg/m3, Mr = 1616.76 and μ = 1.098 mm-1. The antitumor activities of compound 1 and its corresponding organic ligands(bpydb H_2 and Htz) were investigated for inhibiting human osteosarcoma cells(MG-63 and U-2 OS) growth by MTT assay. It was found that compared with the two ligands, compound 1 exerted rather potent activities against all of these cell lines.     

Synthesis and Characterization of Heterobimetallic Zigzag Chains with a Close-packed Structure Based on Macrocyclic Metalloligands

Two new heterobimetallic coordination polymers {[Co(NiL)(H_2O)_3]·4H_2O}_n(1) and {[Cu(NiL)(H_2O)_3]·4H_2O}_n(2) were synthesized based on metalloligand under the same self-assembly conditions. X-ray diffraction analyses reveal that the two compounds involve close-packed zigzag chains, which expand into various three-dimensional supramolecular frameworks through the second interactions such as hydrogen bonds and π···π stacking interactions. In these two compounds, NiL as a bridging ligand chelates the metal ion nodes via two oxamido carbonyls and carboxylate oxygen atom. The central Co(Ⅱ) and Cu(Ⅱ) ions in 1 and 2 both exhibit distorted octahedral coordination geometry. They are bridged by macrocyclic oxamido metalloligands fusing the zigzag chains with a ‘‘head-to-tail' arrangement. The Ni(Ⅱ) ion in metalloligand is coordinated by four nitrogen atoms with the [NiN4] chromophore exhibiting distorted planarity. The two investigated compounds were further characterized by thermogravimetric analysis and FT-IR spectroscopy. The fluorescent properties of 1 and 2 in the solid state were also investigated.     

Effect of pH/Auxiliary Ligand on the Structures of Coordination Compounds Based on a Novel Ligand 2,6-Bis(pyrazin-2-yl)pyridine-4-carboxylate

Four new coordination compounds, [Zn(bppc)_2(H_2O)_2]·3 H_2O(1), [Zn2(bppc)2(mbdc)(H_2O)4]·7 H_2O(2), [Zn(bppc)2(H_2O)2]n·n(m-Hbdc)·n(H_2O)(3), [Zn2(bppc)(btc)(H_2O)3]n·5 n H_2O(4)(Hbppc = 2,6-bis(pyrazin-2-yl)pyridine-4-carboxylate, H2(m-bdc) = 1,3-benzenedicarboxylic acid, H3 btc = 1,3,5-benzene-tricarboxylic acid), have been hydrothermally synthesized and structurally characterized. Compound 1 shows a mononuclear structure and 2 shows a dinuclear structure. Compound 3 is a one-dimensional chain structure, which is extended into a 3D supramolecular network by intermolecular hydrogen interactions. In 4, a 1D loop-like chain is connected by(btc)3-anions to generate a 2D layer structure. The structure differences of 1~4 show that the p H and aromatic acid as auxiliary ligand have important influence on the final structures.iAdditionally, the luminescent properties of 1~4 have been investigated with fluorescent spectra in the solid state, and 1~4 display a strong fluorescent emission at room temperature and have potential applications as fluorescent-emitting materials.     

SYNTHESIS AND STRUCTURE OF TETRANUCLEAR MOLYBDENUM CLUSTER COMPOUND[Mo_4S_4(μ-O_2CC_6H_5)_2(dtp)_4]

The cluster compound[Mo_4S_4(μ-O_2CC_5H_5)_2(dtp)_4](dtp=S_2P(OEt)_2)wasobtained by the ligand substitution reaction of tetranuclear molybdenum cluster[Mo_4S_4(μ-dtp)_2(dtp)_4]in the mixed solvent of acetone,ethanol and water in thepresence of C_6H_5CO_2Na.It is monoclinic and crystallizes in space group C2/c,Mr=1495.09,a=12.175(5),b=22.01(1),c=20.875(9),β=99.04(4)°;V=5575(5);Z=4;Dc=1.78g/cm~3.Final R factor is 0.066.The result reveals that the[Mo_4S_4]clustercore and t-(dtp)~(-1)ligands are retained and only μ-bridged(dtp)~(-1)ligands aresubstituted by(C_6H_5CO_2)~(-1)in the substitution reaction,thus producing the newtitle cluster compound,the structure of which contains two species of bidentateligand.     

Two Co(Ⅱ)-based Coordination Polymers Constructed from π-electron-rich Polycarboxylate Aryl Ether Ligand: Structural Insights and Photocatalytic Dye Degradation

In the present study, two new Co(Ⅱ)-based coordination polymers(CPs) with chemical formulas of {[Co_3(μ_3-OH)(L)(H_2O)_3]·2H_2O}_n(1) and {[Co_3(μ_3-OH)(L)(H_2O)]·_2DMF·3H_2O}_n(2) have been successfully prepared by the reaction of Co(NO_3)_2·6H_2O with π-electron-rich polycarboxylate aryl ether ligand 5,5'-((5-carboxy-1,3-phenylene)bis(oxy))diisophthalic acid(H_5L) under different solvothermal reaction conditions. Both CPs have been studied via single-crystal X-day diffraction, powder X-ray diffraction(PXRD) and thermogravimetric analysis(TGA). The photophysical studies indicated that complex 2 with good water stability is a potential semiconductive material, which could be applied for the degradation of methylene blue(MB) under UV light irradiation and exhibit good stability and recyclability.     

Structure and base properties of calcined hydrotalcites

Five hydrotalcites with Mg/Al molar ratio range of 3-15 were prepared. The structure and basicity of Mg-Al mixed oxides (Mg(Al)O) transformed from hydrotalcites were investigated by TPD, XPS, XRD, FT-IR and NMR techniques. The results of elemental analysis and XPS indicate that Al is enriched in the surface regions of Mg(Al)0, and its amount increases with the Mg/Al molar ratio and the calcination temperature. 27Al-MAS-NMR results show that Al exists in two chemical environments: tetrahedral aluminium (Al(t)) and octahedral aluminium (Al(o)) in Mg(Al)O. The amount of Al(t) increases with the Mg/Al molar ratio and the calcination temperature. It is assumed that Al(t) may be mainly from the surface Al. Temperature-programmed desorption (TPD) of CO2 shows that the number of basic sites of Mg(Al)O samples increases with the Mg/Al molar ratio, and the maximum number of basic sites is obtained for hydrotalcite calcined at 773 K. Infrared spectra of adsorbed CO2 and B(OCH3)3 reveal that there are two kinds of     

THE CRYSTAL STRUCTURE OF YIMENGITE

Yimengite is a new species of mineral discovered in Shandong Province in 1980, with crystal chemical formula K(Cr, Ti, Fe, Mg, Al, Si)_(12)O_(19). It belongs to hexagonal system, and its cell parameters α_0=5.857 and c_0=22.940. 749 separate diffraction intensities of crystal were collected on RASA=IIS auto-four-circle single crystal diffractometer.All atomic coordination, temperature factor and degree of occupation were obtained by RASA-SAP interpretation system, and XTL crystallographic procedure, atomic distances and bond angles for each atom were calculated. Deviation factor R is 0.080.Through the medium of determination of the crystal structure of the new mineral yimengite, coordination form of monovaleace alkali metal element—potassium, etc. in high pressure have been cleared, a five fold coordination form of Fe cations—regular bipyramid has been established, and some new information on the geochemical state of some elements, such as Cr, Ti, etc. have been provided.     

Synthesis,Crystal Structure and Luminescent Property of a Ag(Ⅰ) Coordination Polymer with a 3D Sandwich-like Framework

A new coordination polymer,{[Ag_2(bpp)_2(H_2O)_2]·bpdc·3H_2O}_n,derived from the ligand biphenyl-4,4'-dicarboxylic acid(H_2bpdc),has been obtained through a hydrothermal technique(bpp = l,3-bis(4-pyridyl)propane).Its single-crystal structure has been characterized by single-crystal X-ray diffraction,powder XRD,FT-IR,TGA and elemental analysis techniques.The single-crystal X-ray diffraction reveals that complex 1 consists of 1D infinite[Ag(bpp)(H_2O)]_n~(n+)cationic chains,2D anionic layer constructed by bpdc anions and free water which provide charge compensation in the crystal structure.The 1D infinite[Ag(bpp)(H_2O)]_n~(n+) cationic chains and 2D anionic layer are further stacked in-ABAB- fashion through intermolecular H-bonding to form a 3D sandwich-like framework.In addition,the luminescent property of complex 1 in the solid state at room temperature was investigated.     

Simultaneous assembly of mononuclear and dinuclear dysprosium(Ⅲ) complexes behaving as single-molecule magnets in a one-pot hydrothermal synthesis

Two dysprosium(Ⅲ) complexes derived from 2,2'-bipyridine-6,6'-dicarboxylic acid(H_2bpdc),[Dy(bpdc)(Hbpdc)]-3H_2O(1) and[Dy_2(bpdc)_3(H_2O)_3]·2.125H_2O(2),were isolated from the same hydrothermal reaction container as different phases.Compound1 is a mononuclear complex with a DyN_4O_4 coordination polyhedron;whereas compound 2 is a dinuclear complex with two types of eight coordinated dy sprosium(Ⅲ) ions,showing DyN_4O_4 and DyN_2O_6 coordination polyhedra,respectively.Remarkably,a new type of(H_2O)_6 supramolecular aggregate exists in the crystal structure of 2.Magnetic investigations revealed that 1 is a field-induced single-ion magnet with an effective energy barrier of 45.6 K,exhibiting two-step magnetic relaxation;while an intramolecular ferromagnetic interaction exists in 2,which is a field-induced single-molecule magnet,displaying two-step magnetic relaxation too,with effective energy barriers of 53.4 and 92.1 K,respectively.