排序方式: 共有165条查询结果,搜索用时 790 毫秒
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利用水热法合成了标题配合物Cu4(dhbd)2(dpphen)4•2H2O]•8H2O(H4dhbd=2,3-二羟基丁二酸, dpphen=4,7-二苯基-1,10-邻菲咯啉), 通过元素分析、红外光谱、热分析、X射线单晶衍射等技术对其进行了表征. 晶体结构分析表明, 由于水的配位阻断, 2,3-二羟基丁二酸根仅通过单羟基氧桥联两个U形双核亚单元形成具有一个对称中心的双U形四核结构, 其中U型亚单元包含晶体学上不对称的2个Cu(II)原子、1个2,3-二羟基丁二酸根(dhbd)、2个4,7-二苯基-1,10-邻菲咯啉(dpphen)和1个配位H2O分子. 毗邻的四核单元通过配位H2O分子和配位羟基O原子形成的R22(8)型环形氢键桥的连接, 沿a轴方向构建了四核单元交替相连的一维超分子链; 链间籍苯环的π-π堆积作用和晶格水分子氢键链的连接进一步扩展为具有隧道的三维结构. 配合物中呈现了一种2,3-二羟基丁二酸与过渡金属配位的新方式. 变温磁化率研究表明标题配合物具有弱的反铁磁耦合作用. 相似文献
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在溶剂热条件下,以2-吡啶甲醛肟(HL)为主配体,Zn(OAc)2·2H2O和NiCl2·6H2O为金属盐,合成了一个NiⅡ2ZnⅡ2簇配合物[Ni2Zn2(L)4Cl2(CH3O)2](1),通过元素分析、红外光谱、单晶X射线衍射等对其结构进行了表征。研究了该配合物的磁性及光催化降解染料的性能,结果表明:配合物1属于正交晶系,Pna21空间群,其分子中包含2个NiⅡ离子,2个ZnⅡ离子,4个L-配体,2个Cl-离子和2个CH3O-离子。磁性研究表明NiⅡ…NiⅡ离子间存在弱的反铁磁相互作用。光催化降解染料的研究结果表明该配合物对甲基橙和罗丹明B有较好的降解活性,降解率分别达到83.9%和71.1%。进一步探讨了光催化降解染料的作用机理。 相似文献
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在水热条件下,得到了2例新的配位聚合物[Co(L)0.5(1,3-bib)] (1)和[Ni2(L)(1,4-bib)3(H2O)2]·2H2O (2),其中L=1,2,4,5-苯四酸,1,3-bib=1,3-双((1H-咪唑1-基)甲基)苯,1,4-bib=1,4-双((1H-咪唑1-基)甲基)苯。并利用元素分析、红外光谱、单晶X射线衍射等对其进行了结构表征。结果表明:1和2均为三维网状结构,完全去质子化的配体(L4-)在1和2中分别采取了μ4-к2∶к1∶к2∶к1和μ2-к1∶к0∶к1∶к0的配位方式。进一步的研究表明,配合物1在H2O2和可见光照射的条件下,在水溶液中对染料甲基橙(MO)和亚甲蓝(MB)有很好的降解效果:在180 min时,降解率分别达到83.2%和84.5%。配合物2在同样的条件下,在水溶液中对染料MB和罗丹明B(RhB)也有较好的降解作用:在180 min时,降解率分别为87.0%和77.4%。此外还详细探讨了1和2对染料光催化降解的机理。 相似文献
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A new phase in the MnII–SeIV–MoVI–O system, Mn(MoO3)(SeO3)(H2O) (1), has been hydrothermally synthesized with a high yield (82%), and characterized by IR, TG-DSC, magnetism measurement and single crystal X-ray diffraction. The structure of Mn(MoO3)(SeO3)(H2O) features a complicated 3D network composed of the 1D molybdenum(VI) oxide chains and the 1D manganese(II) selenite chains interconnected via Se–O–Mo and Mn–O–Mo bridges. It is stable up to approximately 340 °C, and losses water molecule at 340 °C, then release SeO2 at about 420 °C. The result of magnetic property measurements has indicated that there exist antiferromagnetic interactions between Mn(II) centers. Photocatalysis experimental result illustrates that the compound exhibits good photocatalytic performance for degradation of RhB under visible light irradiation. 相似文献
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Using the V-shaped oba dianions as bridging ligands and dpa molecules as terminal ligands, a new 1D helical coordination-polymeric chain, [Zn(oba)(dpa)]n [oba=oxybis(4-benzoate), dpa=di(2-pyridyl)amine], was synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, UV-Vis and IR spectra, and TGA analysis. X-ray structural analysis revealed that, oba and dpa ligands played an important role in the self-assembly of the helical chains by providing potential supramolecular recognition sites for π-π aromatic stacking and hydrogen-bond interactions, resulting in the self-assembly of the (4,4) networks to give a 3-D supramolecular framework. The photoluminescence properties of the title compound were also investigated, showing intense blue photoluminescence properties at room temperature. 相似文献
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Abstract. Based on a mononuclear precursor [Mn(Hstp)2(4,4′‐Hbpy)2] ( 1 ), a hetero‐metallic complex, [Mn2Ni(stp)2(4,4′‐bpy)(H2O)4] ( 2 ) [stp = 2‐sulfoterephthalate, 4,4′‐bpy = 4,4′‐bpyridine] was synthesized by solvothermal reaction. Single‐crystal X‐ray diffraction analysis reveals that the MnII ion of the precursor 1 is hexacoordinate by four oxygen atoms from two Hstp2– anions and two nitrogen atoms from two protonated 4, 4′‐Hbpy, and hydrogen bonding plays a significant role in constructing 3D supramolecular structure. While complex 2 features a self‐weaving framework from 1D straight chains and 2D wavy networks with double helical chains. Magnetic behavior of complex 2 was analyzed in connection with its crystal structure, which exhibits the weak antiferromagnetic interactions between the MnII and NiII ions. 相似文献
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A new coordination polymer, [Cu(3, 4‐pybz)2]n ( 1 ) [3,4‐Hpybz = 3‐pyridin‐4‐yl‐benzoic acid], was synthesized by hydrothermal reaction of CuCl2 · 2H2O and 3,4‐Hpybz, and characterized by elemental analysis, IR spectroscopy, PXRD, and single‐crystal X‐ray diffraction. The structure determination reveals that 1 exhibits a 2D twofold interpenetrated 4‐connected (4,4) network topology, these 2D layers are further enlarged to form the final 3D supramolecular edifice via aromatic π–π stacking interactions. In addition, the magnetic behavior and thermogravimetric analysis of 1 were also studied. 相似文献
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Two new PbII metal-organic coordination polymers,namely,[Pb(tda)]n(1) and [Pb(tda)(phen)]n(2)(H2 tda = thiodiglycolic acid,phen = 1,10-phenanthroline),were synthesized under hydrothermal conditions and characterized by elemental analysis,IR,UV spectra,TG technique and X-ray crystallography.Complex 1 crystallizes in the orthorhombic system,space group Iba2 with a = 9.0417(14),b = 19.360(4),c = 7.5741(12),C4H4O4PbS,Mr = 355.32,V = 1325.8(4)3,Dc = 3.560 g·cm-3,F(000) = 1264,μ(MoKa) = 25.711 mm-1,S = 1.086 and Z = 8.The final refinement gave R = 0.0387 and wR = 0.0986 for 3077 observed reflections with I > 2σ(I).Complex 1 is a 2D infinite grid-like(4,4) topological structure constructed by PbII atoms and tda anions,in which tda ligands exhibit bis(syn,syn-bridging bidentate,chelating-bridging tetradentate) mode.Complex 2 crystallizes in the triclinic system,space group P1 with a = 8.3570(17),b = 8.7591(18),c = 10.895(2),α = 76.00(3),β = 80.50(3),γ = 77.61(3)°,C16H12N O4PbS,Mr = 535.53,V = 750.4(3)3,Dc = 2.370 g·cm-3,F(000) = 504,μ(MoKa) = 11.405 mm-1,S = 1.018 and Z = 2.The final refinement gave R = 0.0332 and wR = 0.0629 for 3360 observed reflections with I > 2σ(I).Complex 2 is a 1D chain structure,in which phen ligands are attached on both sides of the 1D chain and tda ligand exhibits a bis(syn,syn-bridging bidentate,chelating tridentate) mode.Finally,complex 2 is extended into a 2D supramolecular structure by strong π···π stacking interactions. 相似文献
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利用沉积法获得了异质结AgI/h-MoO3光催化剂,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、光电子能谱(EDS)、X射线光电子能谱(XPS)、紫外-可见漫反射吸收光谱(UV-Vis-DRS)、光致发光(PL)、电化学阻抗(EIS)等方法对其物相组成、形貌、光吸收特性、光电化学性能等进行了表征。以噻吩的正辛烷溶液模拟催化裂化(FCC)汽油为探针考察了AgI/h-MoO3光催化氧化脱硫活性,结果表明,AgI/h-MoO3-18异质结在催化剂浓度为1.5 g·L-1,可见光照射2 h后,光催化氧化脱硫活性达98%。利用XRD、XPS、UV-Vis-DRS揭示了AgI/h-MoO3光照后生成少量的金属Ag,使其结构转变为Z型AgI/Ag/h-MoO3,有利于光生电子(e-)转移。利用活性物种捕获实验、循环实验研究了AgI/h-MoO3光催化氧化脱硫机理及其稳定性,实验结果表明:AgI/h-MoO3不仅具有较高的光催化氧化脱硫活性,而且还有良好的稳定性。 相似文献