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1.
Self-assembly of lanthanide mixed-carboxylates coordination polymers   总被引:1,自引:0,他引:1  
Two new mixed-ligands lanthanide coordination polymers, [Ln(Ac)(ip)(H2O)2]·0.5H2O (Ln=La (1); Ln=Eu (2); Ac=acetate; ip=isophthalate) have been synthesized under hydrothermal condition. Single-crystal X-ray analyses show that complexes 1 and 2 are three-dimensional structure in which lanthanide ions are bridged by monocarboxylate ligand, acetate or dicarboxylate ligand, isophthalate. And the central lanthanide ions, La3+ and Eu3+, are both nine-coordinate with oxygen atoms. The thermogravimetric analysis was carried out to examine the thermal stability of the title complexes. And the photoluminescence property of complex 2 was also investigated.  相似文献   
2.
Three lanthanide coordination polymers were prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. [Pr2(mBDC)3(phen)(H2O)]n·0.5nH2O (1) (mBDC=isophthalate, phen=1,10-phenanthroline) exhibits two kinds of metal environments (coordination numbers 7 and 8). In complex 1, mBDC ligands adopt the tetradentate (bridging and bridging) coordination mode and connect Pr ions into an undulating layer, and a 3D supramolecular structure is formed via hydrogen bonds between adjacent layers. [Tb4(mBDC)6(phen)]n (2) has three types of metal environments (coordination numbers 6, 7 and 8) and is composed of a 3D network formed by mBDC linking Tb ions via tetradentate (bridging and bridging) and pentadentate (bridging/chelating and bridging) coordination modes. There are two kinds of small quadrilateral channels along the a-axis. [Er4(mBDC)6(phen)]n (3) is isostructural to complex 2.  相似文献   
3.
IntroductionMononuclear ,dinuclearandpolymerictypesofcrys talstructuresforlanthanidecomplexeswithbenzoicacidanditsderivativeshavebeenobtainedbecauseofthevari ationofbridgingformsforcarboxylategroupandcoordina tionabilityofdiammineligands ,suchas 1,10 phena…  相似文献   
4.
A novel microporous coordination polymer [Co2(Hisor)2(4,4′-bpy)2(H2O)2]·4,4′-bpy was synthesized by hydrothermal reaction and characterized by single crystal X-ray diffraction, elemental analysis and IR spectrum. The crystal belongs to the monoclinic system and space group is P2/n with a=1.040 6(3) nm, b=1.138 8(4) nm, c=1.854 7(6) nm, β=102.991(6)°, V= 2.141 6(12) nm3, Z=2, Dc=1.443 Mg/m3, Mr=930.62, μ=0.842 mm-1, F(000)=952, GOF= 1.072, R=0.065 4, wR=0.146 8[I>2σ(I)]. There are two crystallographically independent Co(Ⅱ) ions in the title complex. The Hisor2- and 4,4′-bpy link the metal ions into 2D grids with dimension of 0.522 3 nm×1.138 8 nm. There are O—H…O and N—H…O hydrogen bonds in the complex resulting in the formation of 3D network with 1D channels, in which are free 4,4′-bpy molecules.  相似文献   
5.
A surfactant ion-pair complex, [Ru(bpy)(2)L][Eu(NTA)(4)](2) (in which L = 1-docosyl-2-(2- pyridyl)benzimidazole, bpy = 2,2'-bipyridine, and NTA = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedionato) has been synthesized. The surface pressure-area isotherm measurements show that the complex forms a stable Langmuir film at the air-water interface without adding any electrolytes into the subphase. The monolayers formed at the surface pressures of 5 mN m(-1) and 20 mN m(-1), have been successfully transferred onto glass and quartz substrates with the transfer ratios close to unity. The Langmuir-Blodgett films were studied by UV-visible, infrared, and emission spectroscopies, atomic force microscopy, and cyclic voltammetry. The optical, redox, and morphology properties of the LB films were found to be significantly affected by the target surface pressures used for the film depositions.  相似文献   
6.
The preparation and molecular and crystal structures of the title compound are reported. The compound crystallizes in the triclinic space group (No. 2) with unit cell dimensions of a = 7.2493(3) Å, b = 8.9287(4) Å, c = 10.6594(4) Å, = 90.419(3)°, = 91.287(3)°, = 103.153(3)°, V = 671.62(5) Å3, and Z = 2. The molecular structure of the title compound consists of three sections, the glycine chain and the two 2,5-dioxopyrrolidin-1-ylmethyl groups. Every molecule is linked with three adjacent molecules through three hydrogen-bonding patterns which are 8-membered or 20-membered rings. The chain of rings appears periodically, which makes the molecule form a layer structure in the crystal.  相似文献   
7.
Five new Cu(II) complexes [Cu(psa)(phen)] · 3H2O (1), [Cu(psa)(2bpy)] · 0.5H2O (2), [Cu(psa)(2bpy)(H2O)] · 3H2O (3), [Cu(psa)(4bpy)] · H2O (4), and [Cu(psa)0.5(N3)(2bpy)] (5) (H2psa = phenylsuccinic acid, phen = 1,10-phenanthroline, 2bpy = 2,2′-bipyridine, and 4bpy = 4,4′-bipyridine) were obtained under solvothermal conditions and characterized by single-crystal X-ray diffraction. Complexes 2 and 3 were formed by one-pot reaction. In complex 2, Cu(II) ion is four-coordinated and locates at a slightly distorted square center. In complex 3, the coordinated water molecule occupies the axial site of Cu(II) ion forming a tetragonal pyramid geometry. Complexes 1 and 3 are of 1D chain structures, and extended into 2D supramolecular network by hydrogen bonds. Complex 2 is of zipper structure, and further assembled into 2D supramolecular network by hydrogen bonds and π–π stacking interactions. Complex 4 is a 3D CdSO4-like structure with twofold interpenetration, while complex 5 is a dinuclear compound. The different structures of complexes 15 can be attributed to using the auxiliary ligands, indicating an important role of the auxiliary ligands in assembly and structure of the title complexes.  相似文献   
8.
Hydro- and solvo-thermal reactions of d-block metal ions (Mn(2+), Co(2+), Zn(2+) and Cd(2+)) with monosodium 2-sulfoterephthalate (NaH(2)stp) form six 3D coordination polymers featuring cluster core [M(4)(μ(3)-OH)(2)](6+) in common: [M(2)(μ(3)-OH)(stp)(H(2)O)] (M = Co (1), Mn (2) and Zn (3)), [Zn(2)(μ(3)-OH)(stp)(H(2)O)(2)] (4), [Zn(4)(μ(3)-OH)(2)(stp)(2)(bpy)(2)(H(2)O)]·3.5H(2)O (5) and [Cd(2)(μ(3)-OH)(stp) (bpp)(2)]·H(2)O (6) (stp = 2-sulfoterephthalate, bpy = 4,4'-bipyridine and bpp = 1,3-di(4-pyridyl)propane). All these coordination polymers were characterized by single crystal X-ray diffraction, IR spectroscopy, thermogravimetric and elemental analysis. Complexes 1-3 are isostructural coordination polymers with 3D frameworks based on the chair-like [Zn(4)(μ(3)-OH)(2)](6+) core and the quintuple helixes. In complex 4, there exist double helixes in the 3D framework based on the chair-like cluster cores. Complex 5 possesses a 2-fold interpenetration structure constructed from boat-like cluster core and the bridging ligands stp and bpy. For complex 6, the chair-like cluster cores and stp ligands form a 2D (4,4) network which is further pillared by bpp linkers to a 3D architecture. Magnetic studies indicate that complex 1 exhibits magnetic ordering below 4.9 K with spin canting, and complex 2 shows weak antiferromagnetic coupling between the Mn(II) ions with g = 2.02, J(wb) = -2.88 cm(-1), J(bb) = -0.37 cm(-1). The fluorescence studies show that the emissions of complexes 3-6 are attributed to the ligand π-π* transition.  相似文献   
9.
Li SM  Zheng XJ  Yuan DQ  Ablet A  Jin LP 《Inorganic chemistry》2012,51(3):1201-1203
Five novel 3D heterometallic lanthanide-zinc-organic frameworks, [H(H(2)O)(8)][LnZn(4)(imdc)(4)(Him)(4)] [Ln = La (1), Pr (2), Eu (3), Gd (4), Tb (5); H(3)imdc = 4,5-imidazoledicarboxylic acid; Him = imidazole], were synthesized via an in situ hydrothermal reaction, and tunable luminescence from yellow to white was obtained through the doping of Eu and Tb ions in the La-Zn framework.  相似文献   
10.
N,N二 (N亚甲基 2吡咯烷酮 )丙氨酸是我们最近合成的一个新化合物(如图 1所示),经 X射线衍射实验测定了它的晶体结构,得到了其结构数据。实验结果表明它与稀土离子及其邻菲咯啉形成的配合物具有光致变色的性能。针对该柔性分子具有较复杂的三维构型结构, 为了更好地研究该化合物与金属离子的配位性能,我们基于量子化学 AM1方法的计算结果,从标题化合物分子的几何构型、能量特性、电荷布居、前线分子轨道特征等方面研究了该化合物的配位性能,并与实验进行了比较。 1计算方法 本文根据常见的键长键角数据作为初始化参数…  相似文献   
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