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1.
1 INTRODUCTION In recent years, the syntheses, structures and reactivities of aryloxo lanthanide complexes have attracted a great deal of attention due to their various applications as homogeneous catalysts for organic reactions and precursors for organolan- thanide syntheses[1]. However, the reactivity of divalent lanthanide aryloxides has seldom been studied[2]. We have previously reported that (ArO)2- Sm(THF)4 (ArO = OC6H2-2,6-di-tert-butyl-4-Me) can efficiently initiate the poly…  相似文献   

2.
利用水热合成手段,(2-吡啶甲基)胺基甲基膦酸、草酸盐与醋酸钆(或醋酸铽)配位组装得到2个同构的稀土化合物Ln2(pmampH)(C2O4)2.5(H2O)3.4H2O(Ln=Gd(1),Tb(2))。在2个化合物中,网状的{Ln2(C2O4)2.5}n层通过{LnO8}多面体与{PO3C}四面体的共角连接,形成三维开放结构。沿b方向,可以观察到一维孔道,它们被未配位的(2-吡啶甲基)胺基以及晶格水分子占据。化合物2在部分或全部脱去结构中的配位以及晶格水以后,可以保持它的骨架结构。磁性研究表明化合物1表现出顺磁行为,2则表现出主要的铁磁性相互作用。化合物2以及它的脱水产物的荧光性质也被测定,都表现出Tb(Ⅲ)的特征发射,能够发出绿光。  相似文献   

3.
草酸铽与水合环己烷六酸(H6LⅠ.H2O)(顺式椅式构型LⅠ:a,e,a,e,a,e)在水热条件下反应生成一种新颖的三维稀土配位聚合物[Tb4(LⅡ)(ox)3(H2O)8](LⅡ为反式椅式构型:e,e,e,e,e,e;ox为草酸根),通过元素分析和红外光谱对这个配位聚合物进行了表征。X射线单晶衍射分析表明该配合物属于三斜晶系,P1空间群,晶胞参数为:a=0.60203(4)nm,b=1.08278(8)nm,c=1.29446(9)nm,α=67.908 0(10)°,β=82.109 0(10)°,γ=83.887 0(10)°,V=0.773 07(9)nm3,Z=2。在这个配合物的形成中,顺式构型的H6LⅠ配体发生构型转变形成LⅡ配体,LⅡ配体采取μ8-桥连模式将Tb离子连接成一个具有孔洞的二维(Tb-LⅡ)配位层。由μ2-和μ4-桥连模式构成的一维(Tb-ox)链将二维(Tb-LⅡ)层连接成一个具有孔道的三维配位框架,ox配体和水分子通过配位作用和氢键作用填充在孔道中。  相似文献   

4.
Solvothermal reaction of lanthanide(Ⅲ) salts with fluorescein (2-(6-hydroxy3-oxo-3H-xanthen-9-yl)benzoic acid) led to a series of new coordination polymers {[Ln(C 20 H 11 O 5)(C 20 H 10 O 5)(H 2 O)]·DMF} n (Ln=Er,Eu,Gd,Tb,Tm,Yb).The PXRD patterns of the complexes indicate they are isomorphous.The structure of complex {[Er(C 20 H 11 O 5)(C 20 H 10 O 5)(H 2 O)]·DMF} n has been determined by single-crystal X-ray diffraction,revealing a 2D framework in which DMF molecules were filled between the layers.The crystal structure belongs to the triclinic system,space group P1,with a=12.107(4),b=12.232(4),c=13.273(4),α=68.005(7),β=88.024(11),γ=77.451(8)°,V=1776.7(9) 3,Z=2,D c=1.720 g/cm 3,μ=2.434 mm-1,F(000)=918,R int=0.0584,T=293(2) K,the final R=0.0621 and wR=0.1501.  相似文献   

5.
1 INTRODUCTION In recent years, the assembly of extended supramolecular architectures from molecular building units has yielded a new generation of materials with diverse network topologies[1~6]. A number of such frameworks have been found to exhibit fascinating physical and chemical properties. In particular, much work has been focused on the use of the oxalate ions as bridging ligands to afford two- and three-dimensional homo- and heterometallic assemblies[7~13]. These complexes can…  相似文献   

6.
1 INTRODUCTION The Schiff base ligands have been used to provide a stereochemically rigid ligand framework in homogenous precatalysts of some metals, such as salen Cr catalysts in asymmetric ring-opening re- action of epoxide[1] and salen Al in ring-opening polymerization of lactide and related cyclic esters[2]. Recently, it was reported that the bidentate Schiff base complexes of early and late transition metals can be served as promising alternatives to metal- locene catalysts for th…  相似文献   

7.
合成了一种新的有机磷杀虫剂沙蚕磷[O,O,O',O'-四甲基-S,S'-(2-N,N-二甲氨基-1,3-亚丙基)-双-二硫代磷酸酯],并制备了它的草酸盐。测定了沙蚕磷草酸盐的晶体结构,结果表明,该晶体属三斜晶系,P1空间群,晶胞参数为:a=0.74342(5)nm,b=1.1057(4)nm,c=1.45295(11)nm,α=98.018(11)°,β=101.012(4)°,γ=96.224(10)°,Z=2。通过元素分析,MS、IR及^1H,^1^3CNMR表征了该化合物的结构。  相似文献   

8.
报道2,4-Br2C6H3OCH(CN3)CO2Sn(C6H11)2CU3(1)和2-OCH3-4-CH3CH=CHC6H3OCH2CO2Sn(C6H11)2CH3(H2O)(Ⅱ)的晶体结构和分子结构。(Ⅰ)单斜晶系,空间群P21/c,a=13.067(3),b=10.594(3),c=18.157(4),β=106.99(2)°,Z=4,Dc=1.672g/cm3,V=2403.73,μ=43.731cm-1,Mr=622.99,F(000)=1232;(Ⅱ)单斜晶系,空间群P21/n,a=10.409(1),b= 12.570(2),c=20.664(2),β=83.51(1)°,Z=4,Dc=1.281g/cm3,V=2686.4A3,μ=9.761cm-1,Mr=539.28,F(000)=1120.最后的偏离因子,化合物(Ⅰ)R=0.046,Rω=0.046;化合物(Ⅱ)R=0.049,Rω=0.047。晶体结构解析表明,化合物(Ⅰ)和(Ⅱ)中的锡均被配体的3个碳和2个氧原子配位,配位原子呈畸变三角双锥构型;化合物中的环己基均为椅式构象;化合物(Ⅱ)中,配位水分子和另一分子的羰基氧与芳环上的甲基氧?  相似文献   

9.
1 INTRODUCTION The lanthanide amide complexes are excellent synthetic precursors for lanthanide derivatives, par- ticularly in the reactions involving protonic rea- gents[1]. A few types of lanthanide amide complexes, from homoleptic three- to four-coordinate, have been known for some time[2~4]. Recently, we begin to examine the utility of amide with less steric bulk, such as diphenylamide and diisopropyamide, as li- gands to synthesize homoleptic lanthanide amide complexes. For diphen…  相似文献   

10.
A new tetranuclear square compound (H3O)[Sm2Co2(CDTA)2(DMF)2 (μ4-O) (H2O)6]ClO4 was synthesized through the assembly reaction of Co2+ , Sm3+ and trans-1,2-cclohexylenedinitrilotetraacetic acid (H4CDTA) in aqueous solution. X-ray crystal structural analysis shows that the compound belongs to the monoclinic C2/c space group, with a=27.213(2), b=10.5574(9), c=19.4923(17),β=98.799(1)°, V=5534.1(8)3 , C34H65ClCo2N6O30Sm2 , Mr=1491.93, Dc=1.791g/cm-3 , F(000)=2984,=2.820 mm-1 and Z=4. In the compound, Co2+ is 7-coordianted while Sm3+ is 9-coordinated. With the help of a central O2- and 8 carboxylate oxygen atoms, two Co2+ and two Sm3+ ions are linked into a square with the side length of 3.45 . Magnetic property was investigated.  相似文献   

11.
合成和表征了两种新的Schiff碱配合物[ZnL(ClO4)@4H2O(A)和CdL(ClO4)@3H2O(B)],其中L=2-{[2-(Aminomethyl-amino)-ethylimino]-methyl}-phenol.A(或B)、FeSO4@7H2O和K3[Fe(ox)3]@3H2O进一步反应,生成了配位聚合物{[ML][FeⅡFeⅢ(ox)3]@H2O}∞,其中M=Zn2+(C)或Cd2+(D).红外光谱和Mossbauer谱测定结果表明,C和D具有二维层状结构,其阴离子层由[FeⅡFeⅢ(ox)3]-单元构成.  相似文献   

12.
The first examples of lanthanide(III) organoarsonates, Ln(L(1))(H(2)O)(3) (Ln = La (1), H(3)L(1) = 4-hydroxy-3-nitrophenylarsonic acid), Ln(L(1))(H(2)O)(2) (Ln = Nd (2), Gd (3)), and mixed-ligand lanthanide(III) organoarsonates, Ln(2)(HL(1))(2)(C(2)O(4))(H(2)O)(2) (Ln = Nd (4), Sm (5), Eu (6)), were hydrothermally synthesized and structurally characterized. Compounds 1-3 feature a corrugated lanthanide arsonate layer, in which 1D lanthanide arsonate inorganic chains are further interconnected via bridging L(1)(3-) ligands. Compounds 4-6 exhibit a complicated 3D network. The interconnection of the lanthanide(III) ions by the bridging arsonate ligand leads to the formation of a novel 3D framework with long narrow 1D tunnels along the a-axis, with the oxalate anions are located at the above tunnels and bridging with lanthanide(III) ions. Compounds 2 and 4 exhibit the characteristic emission bands of the Nd(III) ion, whereas compound 6 displays the characteristic emission bands of the Eu(III) ion. The magnetic properties of compounds 3-6 were also investigated.  相似文献   

13.
1 INTRODUCTION Chemistry of manganese cluster has become an attractive research field because of the involvement of manganese in several biological redox-active sys- tems[1,2], especially in the oxygen-evolving complex (OEC) of photosystem Ⅱ (PSⅡ) in green plants[3]. It was thought that the coordination environment of Mn in OEC contains O and N donors, and the bind- ing of aqua to the Mn site may be important to the oxidation of aqua for the evolution of dioxygen[4, 5]. In recent …  相似文献   

14.
The novel mixed-ligand neutral compound [Mo3O4(C2O4)2·bipy(H2O)3]·EtOH·2H2O (bipy = 2,2'-bipyridine) has been prepared by the reaction of oxalic acid elution of Mo(Ⅳ) and bipy, and characterized by single-crystal X-ray diffraction analysis and IR. The crystal is of triclinic, space groups P1 with a = 9.5520(2), b = 10.3730(1), c = 13.5722(2) (A), α = 74.940(12), β = 80.772(14), γ = 69.898(11)°, V = 1215.73(11) (A)3, Z = 2, C16H24Mo3N2O18, Mr = 820.19, Dc = 2.241 g/cm3, μ = 1.616 mm-1, F(000) = 808, T= 293(2) K, the final R = 0.0424 and wR = 0.0939 for 4119 observed reflections with Ⅰ> 2σ(Ⅰ). The trinuclear unit is coordinated by mixed ligands of oxalate and bipy. The intermolecular hydrogen bonding interactions among adjacent [Mo3O4(C2O4)2·bipy(H2O)3] extend the compound into a therr-dimensional supramolecular framework. The uncoordinated water molecules and ethal molecules act as space-fillers and consolidate the whole architecture through hydrogen bonding interactions.  相似文献   

15.
1 INTRODUCTION There has been increasing interest in molecular- based magnetic materials, in which the combination of metal ions and organic radicals are used to construct assembled systems[1, 2]. Nitroxide radicals are normally used as spin carriers …  相似文献   

16.
The title complex (enH2){NH4[Co(en)3][Mo2O7(C2O4)]}2·2H2O (C18H70Co2Mo4- N16O24, Mr = 1396.52) was obtained under hydrothermal conditions and its crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c with a = 17.8023(8), b = 7.7527(4), c = 16.9781(4)A,β= 103.878(7)°, V = 2274.8(2) A3, Dc = 2.039 g/cm3, Z = 2,μ(MoKα) = 1.878 mm-1 and F(000) = 1408. The final R = 0.0410 and Wr = 0.1070 for 4065 observed reflections with I≥2σ(I). The crystal structure is composed of bi- nuclear [Mo2O7(C2O4)]4- anions, complex [Co(en)3]2+ cations, protonated ethylenediamine cations, ammonium cations and crystal water molecules, which are held together into a three-dimensional network via hydrogen-bonding interactions. The binuclear structure of [Mo2O7(C2O4)]4- consist of one MoO4 and one MoO6 octahedra through sharing a bridging oxygen atom, where the oxalate ligand acts as a bidentate ligand coordinating to the octahedral molybdenum atom though two deprotonated corboxylate groups.  相似文献   

17.
A series of lanthanide and lanthanide-transition metal compounds with isonicotinic acid (Hina) and oxalate ligands have been synthesized under hydrothermal reactions. X-Ray crystal structure analyses reveal that they have a rich structural chemistry. Three distinct structure types were exhibited with decreasing lanthanide radii: [LnCu(ina)(2)(C(2)O(4))].H(2)O (Ln=La 1, Pr 2, Nd 3) for type I, [Ln(ina)(C(2)O(4))(H(2)O)(2)] (Ln=Sm 4, Eu 5, Gd 6) for type II, and [Ln(ina)(C(2)O(4))(0.5)(OH)] (Ln=Tb 7, Dy 8, Er 9) for type III. The structure of type I has a 3d-4f heterometallic structure and consists of 1D channels along the b axis, which filled with guest water molecules. They exhibit a first 3D uninodal eight-connected framework with a unique 3(6).4(18).5(3).6 topology. Type II has 2D Ln-ina-C(2)O(4) 4(4)-nets, the nitrogen donors of the ina ligand are not coordinated to any of the metal ions, inducing the lower dimensional networks. Type III consists of 2D Ln-C(2)O(4) layers pillared by ina ligands to form a pillared-layer framework. The structure evolution is due to the versatile coordination modes of ina and oxalate ligands as well as the lanthanide contraction effect. Notably, the oxalate ligand was in situ synthesized from orotic acid through an oxidation-hydrolysis reaction. The type III materials show high thermal stability; luminescence properties of Nd 3, Sm 4, Eu 5, Tb 7 are also investigated.  相似文献   

18.
A novel metal-organic coordination polymer [Mn3(2,2'-dipha)3(phen)6]n·3nH2O (2,2'-dipha = 2,2'-diphenic acid, phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and magnetic susceptibility measurements. The crystal crystallizes in triclinic, space group P1- with a = 16.921(5), b = 18.307(5), c = 18.450(5) (A), α = 113.369(5), β = 108.529(5), γ = 102.984(5)° , V = 4553(2) (A)3, C114H72Mn13N12O14.25, Mr = 2002.66, Dc = 1.461 g/cm3, λ(MoKα)= 0.488 mm-1, the final F(000) = 2058, Z = 2, R = 0.0491 and wR = 0.0980 for 9087 observed reflections (Ⅰ>2σ(Ⅰ)). In the crystal structure, the manganese atom is six-coordinated with two carboxylate oxygen atoms from different carboxylate groups of the same dipha and four nitrogen atoms from two different phen ligands, showing a slightly distorted octahedral geometry. Furthermore, it exhibits a zero-dimensional structure with dipha-Mn-phen- as building units. Variable-temperature magnetic measure shows an overall anti-ferromagnetic behavior for compound 1.  相似文献   

19.
A series of novel trivalent lanthanide complexes, [Ln(2,3‐DMOBA)3(5,5′‐DM‐2,2′‐bipy)]2·C2H5OH (Ln = Eu(1), Sm(2), Gd(3), Ho(4) Er(5), Pr(6), Nd(7)) (2,3‐DMOBA = 2,3‐dimethoxybenzoate, 5,5′‐DM‐2,2′‐bipy = 5,5′‐dimethy‐2,2′‐bipyridine), have been successfully synthesized and structurally validated by single crystal diffraction. All complexes discussed herein feature a binuclear structure, and contain only one free ethanol molecule, which is interesting in the lanthanide complexes. The coordination number of center Ln3+ ions is nine, showing a distorted monocapped square anti‐prismatic coordination geometry. Through a pair of alternating identical C‐H···O hydrogen bonding interactions between two 2,3‐DMOBA ligands on the same lanthanum binuclear unit with 5,5′‐DM‐2,2′‐bipy ligands on two neighboring units, the binuclear complexes can form one‐ The thermal analysis of these complexes are investigated by TG‐DSC/FTIR, the result show that the decomposition process of complexes are mainly divided into four stages with the formation of the respective oxides. The visible light emission experiment of complex 1 is carried out, and the characteristic luminescence behavior of intense red light is exhibited. What'more, fluorescence lifetimes as well as the fluorescent quantum yield of complex 1 is calculated. And the magnetic properties of complexes 3–5 are also studied.  相似文献   

20.
A new bismuth oxalate Na(C5NH6)[Bi(H2O)(C2O4)2]2·4H2O has been obtained under hydrothermal conditions and characterized by X-ray diffraction. It crystallizes in monoclinic, space group C2/m with a = 12.020(5), b = 11.190(8), c = 11.067(10)A, β= 121.78(2)°, NaBi2C13NH18O22, Mr= 981.24, V = 1265.4(16) A^3, Z = 2, Dc = 2.575 g/cm^3,μ(MoKcr) = 14.005 mm^-1, F(000) = 912, R = 0.0179 and wR = 0.0394. In the structure, the Bi(III) centers are interconnected by oxalate ligands to produce honeycomb-like layers, which are further pillared by bridging ligand oxalate molecules to form a 3-D open-framework structure. Furthermore, the title compound exhibits blue luminescence with the emission peaks located at 394nm in the solid state at room temperature, and thus it could be useful in the field of photoactive materials.  相似文献   

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