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1.
A novel bimetallic 4f-3d metal-isonicotinic acid inorganic-organic hybrid complex [Tb0.5(C6NO2H5)3(H2O)2]2n ·(H3O)4n (ZnCl5) n (ZnCl4)2n (1) is synthesized. It has a one-dimensional polycationic chain-like structure. Photoluminescent investigation reveals that it displays interesting emissions in the violet, blue, green, and yellow regions.  相似文献   

2.
C om m ent Silver and zinc salts of sulfadiazine are widely used to prevent bacterial infection for both hum ans and anim als during burn treatm ents[1~4]. Because the slow release of the m etal ions highly relevant to the biologicalactivity ofthese polym…  相似文献   

3.
4.
The method of synthesis of the hitherto unknown class of organosilicon compounds, phenyl(acyloxy)fluorosilanes C6H5Si(OCOR) n F3−n (n = 1, 2) and phenyl(acyloxy)fluorochlorosilanes C6H5Si(OCOR) FCl in up to 91% yield has been developed based on the reaction of phenyl(fluoro)chlorosilanes C6H5SiCl n F3−n (n = 1, 2) with trimethylsilyl esters of carboxylic acids Me3SiOC(O)R [R = H, CH3, CF3, CCl3, ClCH2, BrCH2, CH2=CHCH3, CH2=CHPh, CH(CH3)=CH2, Ph].  相似文献   

5.
A novel inorganic-organic hybrid complex, [Nd [Nd (C6NO2H5)3(H2O)2]2n · (nH5O2)(nHgCl5)(2nHgCl4) · (nH2O)(1), was obtained by hydrothermal reactions and structurally characterized by X-ray diffraction. The unit cell parameters are as follows: a = 9.579(1), b = 21.462(2), c = 15.801(1) ?, β = 102.339(6), V = 3173.5(5) ?3, Z = 4, space group P21/c. The crystal structure analysis reveals that the title complex is characteristic of a novel polycationic [Nd(C6NO2H5)3(H2O)2]2n 6n+ one-dimensional chain-like structure. Photoluminescent investigation shows that the title complex displays strong emission in blue region, which is attributed to the intraligand π-π*-transition of nicotinic ligands. Optical absorption spectra of 1 reveal the presence of an optical gap of 3.45 eV. The article is published in the original.  相似文献   

6.
Homoleptic mononuclear and binuclear ruthenium carbonyls Ru(CO) n (n = 3–5) and Ru2(CO) n (n = 8,9) have been investigated using density functional theory. Sixteen isomers are obtained. For Ru(CO)5, the lowest-energy structure is the singlet D 3h trigonal bipyramid. Similar to Os(CO)5, the distorted square pyramid isomer with C 2v symmetry lies ∼7 kJ·mol−1 higher in energy. For the unsaturated mononuclear ruthenium carbonyls Ru(CO)4 and Ru(CO)3, a singlet structure with C 2v symmetry and a C s bent T-shaped structure are the lowest-energy structures, respectively. The global minimum for the Ru2(CO)9 is a singly bridged (CO)4Ru(μ-CO)Ru(CO)4 structure. A triply bridged Ru2(CO)6(μ-CO)3 structure analogous to the known Fe2(CO)9 structure is predicted to lie very close in energy to the global minimum. For Ru2(CO)8, the doubly bridged C 2 structure is predicted to be the global minimum. For the lowest-energy structures of M2(CO) n (M = Fe, Ru, Os, n = 9,8), it is found that both iron and ruthenium are favored to form structures containing more bridging carbonyl groups, while osmium prefers to have structures with less bridging carbonyl groups. The study of dissociation energy shows that the dissociation of Ru2(CO)9 into the mononuclear fragments Ru(CO)5 + Ru(CO)4 is a less energetically demanding process than the dissociation of one carbonyl group from Ru2(CO)9 to give Ru2(CO)8.  相似文献   

7.
A new polymer azido-bridged copper(II) complex [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2] n (I) (En = ethylenediamine) has been synthesized and crystallography characterized. Complex I shows one-dimensional coordination polymeric structure based on a tetranuclear cluster unit [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2], in which the azido ions display three different bridging modes.  相似文献   

8.
The molecular structure and magnetic properties of alkoxy-polyoxovanadates [VIV n VV 6−n O7(OR)12]4−n (n = 4, 3, 2) were studied within the framework of the DFT approach. The equilibrium geometric configurations of all complexes studied in this work are characterized by a distorted octahedral hexavanadate core; the unpaired d-electrons are localized on the metal centers (VIV). The localized spin density distribution is also retained in the low-temperature crystal structures of the compounds whose magnetic properties are described by the Heisenberg-Dirac-van Vleck exchange spin Hamiltonian. The exchange parameters calculated using the broken symmetry formalism suggest predominance of ferromagnetic coupling between vanadium(IV) ions in the μ-OR bridged dimeric units {VIVO(OR)VIV} and in the diagonal pairs {VIVOVIV} (n = 4). The results obtained indicate that the magnitude and sign of the exchange parameters in the isostructural dimeric units within the hexavanadate core depend on the total number of unpaired electrons in the system.  相似文献   

9.
配位超分子聚合物的设计合成与应用研究一直是配位化学、超分子化学、生物无机化学及材料科学等领域的热点研究课题之一,具有微孔结构的配位聚合物吸引了许多科学家的目光,这不仅因为该类配合物具有新颖的结构,展现出多种诱人的拓扑结构,更主要的 是因为它们在离子交换、催化、磁性材料、光学材料及气体贮存领域的应用潜力[1~3].  相似文献   

10.
A novel heterotrimetallic complex {[(Dipic)2Cu]4 · Mg(H2O)2Na4(H2O)14 n · nNa2(H2O)10 · 2nCH3OH (H2Dipic = pyridine-2,6-dicarboxylic acid) has been synthesized and structurally determined by X-ray diffraction method. The compound crystallizes in the triclinic system, space group P [`1]\bar 1, with a = 13.5523(13), b = 14.1859(13), c = 14.3213(14) ?, α = 62.6160(10)°, β = 68.2540(10)°, γ = 89.7110(10)°, V = 2224.7(4)?3, F(000) = 1144, M r = 2237.70, Z = 1, ρ c = 1.670 g cm−3, μ = 1.095 mm−1, final R = 0.0507, wR = 0.1418 for 8042 independent reflections with R int = 0.0228. According to the structure determination, the complex is composed of novel one-dimensional (1D) alternating chains, dinuclear Na(I) units, and lattice methanol molecules. The infinite 1D chain structure is built up with many of polymeric [(Dipic)2Cu]4 · Mg(H2O)2Na4(H2O)14 units, which consists of four six-coordinated Cu2+ ions, one six-coordinated Mg2+ ion, two five-coordinated Na+ ions, and two six-coordinated Na+ ions. The 1D alternating chains are linked with another dinuclear Na(I) units by extensive hydrogen bonds to form a three-dimensional (3D) supramolecular structure in which uncoordinated methanol molecules act as space filling particles.  相似文献   

11.
Al synthesized samples are isostructural and crystallize in the orthorhombic symmetry system, space group Ibca. Particles of the final product of ∼200 nm in size have been obtained. The introduction of the vanadate anion into the matrix composition leads to the lowering of the symmetry of the Eu3+ environment and to the rise of the defect luminescence at 450–550 nm because of the unit cell distortion. The luminescence of defects in terbium-europium-containing samples is determined by the sample surface area, which decreases on annealing. The τ, W 0 and γ parameters of the luminescence kinetics of the samples have been determined.  相似文献   

12.
The novel 3D coordination polymer {Cd2(C4H2O4)2(C4H6N2)2(H2O)2 · 2H2O} n (I) has been synthesized and characterized by standard solid state methods including single-crystal X-ray crystallography. The compound crystallizes in triclinic space group P [`1]\bar 1 with a = 8.589(4), b = 10.585(3), c = 13.094(1) ?, α = 84.91(4)°, β = 79.21(0)°, γ = 83.76(4)°, V = 1159.5(1) ?3, Z = 2. The fumaric acid acts as a multimodal bridging ligand in the polymer unit. One of the fumaric acid ligands tridentately chelates to two Cd2+ cations in the same dinuclear unit, while the other bidentately chelates to two Cd2+ cations in another dinuclear unit. The two metal centers possess slightly distorted pentagonal bipyramid geometry with four Cd {(μ4-fumarato)-(μ2-fumarato)-bis(2-methylimidazolyl)-diaqua} units joining together to form a 28-membered ring. The whole molecule exhibits a through channel along y-axis and 2D layers in xz plane. With hydrogen bond and π-π interaction, the 2D layers construct a 3D microporous network.  相似文献   

13.
C60Co(Pph3)2的合成和表征   总被引:1,自引:0,他引:1  
The fullerene complexe C60Co(Pph3)2 has been prepared by the reaction of C60 with CoCl2(Pph3)2 under a nitrogen atmosphere and refluxing, and characterized by elemental analyses, FT-IR, XPS, NMR, which appove that C60 coordinates to Co(Pph3)2 group in σ-π pattern and the electron is super conjugate over whole molecule. The result of redox property study show that the reduction potentiel of C60Co(Pph3)2 is more negative than that of C60, the reason may be the π electron dentensity of C60 in C60Co(Pph3)2 increases, which lead to it′s electron affinity decreasing. The thermostability experiment indicates that the oxidation decomposition temperature of C60Co(Pph3)2 is lower than that of pure C60.  相似文献   

14.
In order to determine the features of the structure of double complex salts (DCSs) of [Cr(NH3)5Cl]×[MCl4nH2O, where M = Pd, Pt, n = 0, 1, the DCS solid solutions of palladium and platinum with isostructural DCSs containing the chloropentaammine rhodium cation, [Cr(NH3)5Cl] x [Rh(NH3)5Cl]1−x [MCl4nH2O, where x = 0.01–0.2, are synthesized and studied by the EPR method. DCSs with the isostructural chloropentaammine rhodium cation are used as a diluter for magneto concentrated systems. It is shown that DCS of platinum and anhydrous DCS of palladium have the identical environment of chromium ions. The EPR spectra of chromium ions for these compounds are described by the following spin Hamiltonian parameters: S = 3/2, g xx = 1.987, g yy = 1.987, g zz = 1.985, D = 1660 Gs, E = 235 Gs. For the palladium complex containing crystalline water, the EPR spectra of chromium ions are described by the parameters: S = 3/2, g xx = 1.984, g yy = 1.984, g zz = 1.984, D = 1060 Gs, E = 350 Gs. A decrease in the crystal field parameters for the aqueous palladium complex is caused by a redistribution of the electron density to the oxygen atom in the second sphere of the chromium ion environment.  相似文献   

15.
In the title compound, [Pb2(C8H4O4)2(C19H12N4O)2]n·3.5nH2O(1), has been synthesized by the hydrothermal assembly of 1,4-benzenedicarboxylate and 4-(1H-1,3,7,8-tetraazacyclopenta[l]-phenanthren-2-yl)phenol(TCPP) with lead acetate. Elemental analysis, X-ray crystal structure analysis, IR spectrum, thermogravimetric analysis and luminescence property were carried out for the structural determination and characterization of the title compound. Compound 1 crystallizes in triclinic, space group P1 with a=1.013 54(10) nm, b=1.104 84(11) nm, c=1.210 05(12) nm, α=76.812 0(10)°, β=74.814 0(10)°, γ=86.030 0(10)°, V=1.273 1(2) nm3, Pb2C54H39N8O13.5, Mr=1 430.31, Z=1, Dc=1.866 g·cm-3, μ=6.680 mm-1, F(000)=691, R=0.027 3 and wR=0.068 7 for 4 042 observed reflections (I>2σ(I)). The compound 1 exhibits two-dimensional network structures, which are further stacked through π-π interactions and hydrogen bonds to form three-dimensional supramolecular polymer. Solid-state luminescent spectrum of the compound 1 indicates intense fluorescent emission. CCDC: 748883.  相似文献   

16.
配合物Fe(pda)2(H2O)4和[FeCo(pda)4(H2O)4]n的合成与晶体结构   总被引:1,自引:0,他引:1  
采用水热法合成了2个3-(3-吡啶基)丙烯酸的配合物:Fe(pda)2(H2O)4(1)和[FeCo(pda)4(H2O)4]n(2)(pda=3-(3-吡啶基)丙烯酸),用红外光谱、元素分析、热重-差热以及X-射线衍射单晶结构分析进行了表征.2个配合物都属于单斜晶系,配合物1的空间群为P21/n,配合物2的为P21/c.配合物1是一个pda配体中仅吡啶基氮原子参与配位、而羧基上的氧原子未参与配位的单核结构,通过大量的氢键作用形成三维超分子体系.2是pda配体桥联Fe和Co的异核二维层状配位聚合物;配体吡啶基上的氮原子和羧基上的氧原子都参与了配位,其中羧基采用单齿配位模式.  相似文献   

17.
The title compound, [Mn3(L)6(CH3OH)2]n·0.5nH2O (1), where HL=3,5-dirnethylbenzoic acid, was synthesized and its crystal structure was determined by X-ray diffraction structure analysis. The crystal is of triclinic,space group P1 with α=1.275 1(13) nm, b=1.354 6(14) nm, c=1.882 3(19) nm, α=110.826(1)°,β=94.358(2)°,γ=108.038(1)°, V=2.825 4(5) nm3, Z=1, Mr=2 265.77, Dc=1.332 g·cm-3,μ=0.723 mm-1, F(000)=1180, Rint=0.037, R=0.056 4, wR=0.128 5. In the crystal the manganese atom is six-coordinated by six oxygen atoms, completing an octahedral geometry. The molecules are connected by 3,5-dimethylbenzoic acid to form a 1D chain structure bridged. CCDC: 694097.  相似文献   

18.
Two modifications of the new uranyl oxalate hydroxide dihydrate [UO2)2(C2O4)(OH)2(H2O)2] (1 and 2) and one form of the new uranyl oxalate hydroxide trihydrate [(UO2)2(C2O4)(OH)2(H2O)2]·H2O (3) were synthesized by hydrothermal methods and their structures determined from single-crystal X-ray diffraction data. The crystal structures were refined by full-matrix least-squares methods to agreement indices R(wR)=0.0372(0.0842) and 0.0267(0.0671) calculated for 1096 and 1167 unique observed reflections (I>2σ(I)), for α (1) and β (2) forms, respectively and to R(wR)=0.0301(0.0737) calculated for 2471 unique observed reflections (I>2σ(I)), for 3. The α-form of the dihydrate is triclinic, space group , Z=1, a=6.097(2), b=5.548(2), , α=89.353(5), β=94.387(5), γ=97.646(5)°, , β-form is monoclinic, space group C2/c, Z=4, a=12.180(3), b=8.223(2), , β=95.817(4), . The trihydrate is monoclinic, space group P21/c, Z=4, a=5.5095(12), b=15.195(3), , β=93.927(3), . In the three structures, the coordination of uranium atom is a pentagonal bipyramid composed of dioxo UO22+ cation perpendicular to five equatorial oxygen atoms belonging to one bidentate oxalate ion, one water molecule and two hydroxyl ions in trans configuration in 2 and in cis configuration in 1 and 3. The UO7 polyhedra are linked through hydroxyl oxygen atoms to form different structural building units, dimers [U2O10] obtained by edge-sharing in 1, chains [UO6] and tetramers [U4O26] built by corner-sharing in 2 and 3, respectively. These units are further connected by oxalate entities that act as bis-bidentate to form one-dimensional chains in 1 and bi-dimensional network in 2 and 3. These chains or layers are connected in frameworks by hydrogen-bond arrays.  相似文献   

19.
The complex, [Cu2(L-ala)2(phen)2]n·2nClO4·2nH2O(L-ala=L-alaninate, phen=1,10-phenanthroline) has been synthesized and investigated by elemental analysis, IR spectroscopy, and X-ray diffraction methods. The complex crystallizes in the monoclinic space group P21 with a=1.161 1(4) nm, b=0.717 2(2) nm, c=2.074 1(7) nm, β=101.028(6)°, V=1.695 4(9) nm3, Dc=1.760 g·cm-3, Z=4, μ=1.493 mm-1, F(000)=916, R=0.052 2, wR=0.127 9 for 7 131 unique reflections. The cations of [Cu2(L-ala)2(phen)2]n2n+ have an one-dimensional polymeric structure, due to the bridging of two Cu(phen)2+ units by a carboxylate group of L-alaninate, and each Cu(Ⅱ) ion is in a slightly distorted square-pyramidal coordination geometry, with the phen (N,N′) and the L-ala(N,O) acting as bidentate ligands in the equatorial plane and another carboxylate oxygen atom from a symmetry-related neighboring L-alaninate ion in the apical position. CCDC: 277541.  相似文献   

20.
The title complex, [CaCu(C3H2O4)2(H2O)4]n, with a formula of C6H12CaCuO12 and Mr=379.78 has been sy-nthesized and characterized by single crystal X-ray diffraction structure analysis, elemental analysis, IR spectra and TG-DTG techniques. The results show that the crystal is Orthorhombic, space group Pbcn with a=0.669 21(5) nm, b=1.370 23(5) nm, c=1.322 39(10) nm, V=1.212 59(16) nm3, Dc=2.080 g·cm-3, μ=2.288 mm-1, F(000)=772 and Z=4. The final R=0.054 0 and wR=0.112 8 for 1 189 observed reflections with I>2σ(I). The structure of the title complex consists of CaO8 polyhedra and CuO6 elongated octahedra linked together by malonate ligands. The Ca(Ⅱ) cation, on a twofold axis, is coordinated by two water molecules and six malonate O atoms. The Cu(Ⅱ) cation, which lies in a centre of symmetry in an octahedral arrangement, is coordinated by four malonate O atoms and two water molecules. The structure comprises alternating layers along the [101] plane, with the shortest Cu…Cu distance of 0.762 46(6) nm. The whole 3D structure is maintained and stabilized by the presence of hydrogen bonds. Its thermo gravimetric analysis was determined by TG-DTG techniques. CCDC:663184.  相似文献   

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