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1.
本文报道了Ln(DBM)_3·H_2O的简正坐标分析结果, 计算中采用了单螯合坏近似模型, 计算结果和红外、拉曼光谱观测频率符合较好, 所得到的一组力常数, 具有较好的转移性质. 讨论了一些重要谱带的性质。  相似文献   

2.
<正> Ln(o-HOC6H4CO2)3(H2O)2·2H2O [Ln = Tb, Ho], Mr = 642. 32 (648. 33 )**,monoclinic, space group Cc,a=16. 280(4)(16. 217 (2)) ,b= 14. 889(3) (14. 877(2)),c = 9.867(1)(9. 835(2)) A,β=101.49(1)(101. 46(1))°,Z= 4,V= 2343. 8(7)(2325. 3(6)) A3,Dc=1. 8(1. 85)g·cm-3,μ=31. 6(36. 1)cm-1(MoKa), F(000) = 1272(1280).The final R=0. 031(0. 031),Rw = 0. 029(0. 031). There is no discrete molecules of the compounds in the crystal structures. The compounds are in linear polymeric arrangements, each metal ion is bridged to the next by two bridging carboxyl groups from salicylato ions.  相似文献   

3.
合成了希土高氯酸盐开环冠醚二缩乙二醇(EO2)晶体,(Ln=Nd,Ho),测定了结构,文内以Nd-L的数据为主要研究对象(方括号内是Ho-L的数据)。晶体属单斜晶系,P21/n空间群,化学式[Ln(EO2)3](ClO4)3·3H2O,晶胞参数为:a=14.124(1)[14.087],b=13.990(1)[14.039],c=15.265(1)[15.014];β=95.78(1)[95.64]°;V=3001.1(6)[2955]3;Mr=815.01[835.70];Z=4;Dc=1.804[1.865]g/cm3;石墨单色器,μ(MoKα)=2.09[3.07]mm-1,最终偏离因子R=0.055[0.074],RW=0.071[0.109]。研究结果表明晶体具有相同的结构,配位多面体为九配位三帽三棱柱。发现EO2醚链有绕C-C键呈STTS分布的规律。弱配体高氯酸根不参加配位。  相似文献   

4.
Ln(p-ABA)_3bpy·2H_2O的合成、晶体结构和光谱分析   总被引:4,自引:1,他引:4  
报道了Ln(p-ABA)_3bpy·2H_2O(Ln=Nd,Eu,Yb)的合成和晶体结构、拉曼光谱及荧光光谱的测定。晶体属三斜晶系,P(?)空间群。中心原子配位数为8。羧基具有单齿、螯合双齿和桥式3种配位方式。配合物的拉曼光谱与晶体结构测定结果吻合。Eu(p-ABA)_3bpy·2H_O的高分辨激发光谱和发射光谱表明,Eu(Ⅲ)离子仅有一种晶格格位,中心离子具有C_1格位对称性。  相似文献   

5.
<正> Biaqua-trichloroacetate-samarium dihydrate, [Sm(CCl3COO)3(H2O)2]-2H2O, Mr=707.54, orthorhombic, space group Pnne, with a = 19.158(5), b = 22.176(4), c= 9.798(4)A, Z= 8, V= 4162.7A3.F{000)= 2696,λ(MoKα)=0.71069A, Dx = 2.258 g/cm3, final R=0.061. The title compound has non-molecular structural character, and its structural units Sm(μ-CCl3COO)s/2-(H2O>2 constitute 2-dinensional infinite chains of Sm(μ-CCl3COO)4Sm(μ-CCl3-COO)2Sm.The Sa(Ⅲ) atom in each unit is bound to two O atoms from aqua-molecules and six 0 atoms from six bridging CCl3COO groups (four of which are shared with the SB atom of another unit, two shared with the Sm atom of a third unit) forming a square antiprism.  相似文献   

6.
标题配合物在水溶液中合成 ,缓慢挥发水溶液 ( p H=4~ 5)得到其针状单晶 .研究了配合物的热分析与红外光谱 ,测定了配合物的晶体结构 .结果表明 ,晶体属正交晶系 ,空间群 P2 12 12 1,晶胞参数为 :a=1 .1 960 ( 2 ) nm,b=3 .0 789( 6) nm,c=0 .4 7652 ( 1 0 ) nm.V=1 .7547( 1 6) nm3 ,Z=4 ,Dc=1 .987g/cm3 .晶体是一维链状配合物 .相邻 Gd3 离子通过 2个简单羧基桥和 1个μ2 羧基桥联结起来 ,还有 2个水分子配位于每个 Gd3 离子 ,所以 Gd3 的配位数为 9,形成变形的单帽四方反棱柱体 .该配位多面体是摩尔比为 1∶ 3的稀土甘氨酸配合物中报道的第 1个例子 .得到了该配合物的配位键的键焓  相似文献   

7.
A uranylcontaining compound [U(CO_3)_3(H_2O)_2]·2H_2O has been synthesized under hydrothermal condition and characterized by X-ray single-crystal analysis. Crystal structural analysis indicates that this compound consists of three CO_3~(2-) molecules, one U~(6+). The results reveal that the title compound presents a 3D frame work built up by O-H……O week hydrogen bonds interactions. The central uranium atom is eight-coordinated through three CO_3~(2-) molecules and two H_2O. The compound shows a coplanar hexagonal network structure, each hexagon containing a hexagonal hole with a water moleculet.  相似文献   

8.
The heat capacities of four RE isothiocyanate hydrates,Sm( NCS)3 6H2O,Gd( NCS)3 6H2O,Yb(NCS)3 6H2O and Y( NCS)3 6H2O,have been measured from 13 to 300 K with a fully-automated adiabatic calorimeter No obvious thermal anomaly was observed for the above-mentioned compounds in the experimental tem-peiatnre ranges.The polynomial equations for calculating the heat capacities of the four compounds in the range of 13-300K were obtained by the least-squares fitting based on the experimental Cp data.The Cp values below 13 K were estimated by using the Debye-Einstem heat capacity functions.The standard molar thermodynamic functions were calculated from 0 to 300 K.Gibbs energies of formation were also calculated.  相似文献   

9.
本文利用水热合成方法,将稀土氧化物与邻苯二乙酸(H2pda)反应得到了2个新颖的稀土配位聚合物{[Ln2(pda)3(H2O)2]·2H2O}n(Ln=Nd(1),La(2))。测定了它们的晶体结构,并进行了X-射线单晶衍射、红外光谱、荧光光谱和热重分析等性质的表征。晶体结构测定表明这2个化合物为异质同晶化合物。属单斜晶系,C2/c空间群。晶体学参数分别为配合物1:a=2.629 06(18)nm,b=1.611 72(11)nm,c=0.783 27(5)nm,β=93.173(5)°,V=3.313 9(4)nm3,Z=4,F(000)=1 840,μ=3.173 mm-1,Dc=1.878 g·cm-3,R1=0.022 6,wR2=0.060 9;配合物2:a=2.627 1(14)nm,b=1.614 9(8)nm,c=0.796 6(4)nm,β=92.850(9)°,V=3.375(3)nm3,Z=4,F(000)=1 816,μ=2.570 mm-1,Dc=1.823 g·cm-3,R1=0.0466,wR2=0.1416。化合物中邻苯二乙酸配体连接相邻的稀土金属离子,形成复杂的具有stp拓朴构型的三维网络结构。  相似文献   

10.
11.
以Ln(NO3)3、H2pzdc(2,3-吡嗪-二羧酸)和prz(哌嗪)为原料,在水热条件下得到了2个结构新颖的稀土配位聚合物{(H2prz)[Ln2(pzdc)4(H2O)2]·5H2O}n(Ln=Eu(1),Tb(2))。对它们进行了元素分析、红外光谱、粉末X-射线衍射、热重等分析,并用X-射线衍射测定了它们的单晶结构。2个配合物的晶系都属于三斜晶系,P1空间群。研究了它们的荧光性质,固体荧光实验测试结果表明,2个配合物在室温下均表现出相应稀土离子的特征荧光发射。  相似文献   

12.
用全自动绝热量热计测定了4种稀土异硫氰酸盐六水合物,Sm(NCS)_3·6H_2O,Gd(NCS)_3·6H_2O,Yb(NCS)_3·6H_2O和Y(NCS)_3·6H_2O在13~300 K间的热容,在实验温区上述化合物均未发现反常热容.根据实验热容数据用最小二乘拟合方法得出了计算这4种化合物在13~300 K温区内的热容多项式方程.13K以下的热容用 Debye-Einstein热容函数估算而得.计算了这些化合物在0~300 K间的标准热力学函数及其标准生成Gibbs能.  相似文献   

13.
<正> The title compound C6H16O9Fe, Mr = 288. 13, was synthesized and crystallized in monoclinic space group P21/c, a = 9. 409(4), b = 5. 812(4), c= 22. 122(7)(?) , β=90. 80(3)°. V = 1209. 6(?)3, Z = 4, Dc=1. 572g/cm3, F(000) = 592, μ = 12. 73cm-1, R = 0. 063, Rw= 0. 068 for 1191 observed reflections. The iron atom is surrounded by O(1 - 6) in a distorted octahedron.  相似文献   

14.
将MnCO3 与2,4,6-三硝基间苯二酚(斯蒂芬酸、TNR)分散于蒸馏水中, 加热搅拌制备出斯蒂酚酸锰溶液,再与碳酰肼(CHZ)水溶液反应制备〔Mn2 (TNR)2(CHZ)2(H2O)4〕·2H2O(C14H26Mn2N14O24, Mr= 884.36),并对其进行了元素分析和红外表征,利用单晶分析测定了晶体结构。该化合物为双核配合物,属三斜晶系,空间群为P1,晶体学数据如下:a= 7.280(1),b= 10.318(1),c= 11.106(1),α= 94.56(1),β= 91.86(1),γ= 106.88(1)°,V= 794.4(2)3,Z= 1,Dc= 1.849g.cm - 3, μ=9.15cm - 1, F(000)= 450, I> 2σ(I)的独立可观测点个数为2783,最终偏离因子R=0.0272, Rw = 0.0639。分子为中心对称,配位多面体为略有畸变的五角双锥体构型。  相似文献   

15.
<正> C12H34O20Eu2,Mr=802.30 triclinic, space group P1, a= 8.955(2), b=9.328(1), c=10.536(2) A,α= 91.74(2),β=113.87(2),γ=118.23(2), V=681.7(2)A,Dm(flotation in CC14/ BrCH2CH2Br)=1.95,DX(Z=1) =1.954g cm-3,λ(MoKα)=0.71069 A,μ=6.41 cm-1,F(OOO)=391.92, T =. 295°K,final RF= 0.032 for 7483 observed reflections with |F0|>3a(|Fo|). The compound is isostructural with the known erbium complex,the basic unit being a centrosymmetric dimer composed of two nine-coordinate polyhedra sharing a common edge. An O atom in one or the three bidentate acetato groups about each europium atom serves as a bridge between the metal centars. The dimeric units are linked by hydrogen bonds involving both ligand and lattice water molecules to form a three-dimensional network.  相似文献   

16.
含Eu(DBM)_3·H_2O纳米微晶的光学树脂的制备及性能研究   总被引:5,自引:0,他引:5  
稀土β二酮的配合物因其具有Antenna效应,发光强度明显增强;而且它的激光性质也被证实[1] ,是应用价值极大的配合物.稀土配合物与高分子的复合,获得了兼具二者优良性能的功能材料,有很好的应用前景.通常二者的复合多采用直接掺杂、机械共混和熔融等方法.但由于二者的相容性较差,并且存在着浓度淬灭现象,使获得高稀土含量、分散均匀的聚合物发光材料非常困难.以往,杨柏小组分别采用直接掺杂和原位复合的方法制备了含稀土配合物的光学树脂[2 ,3 ] ,但稀土配合物含量受到限制.本文在文献[4,5 ]的基础上,采用化学沉淀的方法,制备了30~30 0nmEu…  相似文献   

17.
1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2~9].But up to…  相似文献   

18.
采用水热法合成了新的配合物[Ni(H2O)6].[Ni2(phen)2(BTC)2(H2O)4].4H2O(phen=邻菲啰啉;BTC=均苯三甲酸),采用X射线单晶衍射结构分析及元素分析、红外光谱等表征,并用TGA检测了该配合物的热稳定性.晶体属于三斜晶系,空间群为P-1,晶胞参数a=0.84038(7)nm,b=0.92048(8)nm,c=1.64793(14)nm,α=97.3850(10)°,β=102.7930(10)°,γ=104.9700(10)°,V=1.17736(17)nm3,F(000)=622,Z=1.标题化合物的不对称结构是由NiO6单元和1个二聚物Ni2N4O12单元组成的,该二聚物单元通过2个邻菲啰啉和2个均苯三甲酸分子构筑了1个八元环.氢键将2个独立的结构单元连接成三维结构.  相似文献   

19.
三羟甲基氨基甲烷与苦味酸(Pic)镍在乙醇水混合液中反应,制得少见的半 对称分叉氢键连接的超分子化合物Ni[H_2NC (CH_2OH)_3]_2·(H_2O)_2·(Pic)_2 ,晶体属三斜晶系,空间群为P(1-bar),晶胞参数为a = 0.6912(1) nm,b = 0. 8190(1) nm,c = 1.3595(2) nm,α = 79.59(1)°,β=83.69(1)°,γ = 83. 77°,V = 0.74925(18) nm~3, Z = 2,F(000) = 410。在配合物的结构单元中, Ni~(2+)位于对称中心,分别与两个四齿配体(三羟甲基氨基甲烷)中的两个-OH ,一个-NH_2,三齿配位,呈笼状螯合。而另一个-OH,因配体和中心离子构型的 限制,不参与配位。运用Gaussian 98量子化学程序包,对该配合物进行从头算研 究,探讨了此配合物的稳定性、原子净电荷分布,并对分子识别、分子间与分子内 交互作用进行了讨论,为该类配合物的合成、分子组装研究提供理论参考。  相似文献   

20.
Introduction Flavonoids exist widely in edible plants, and have pharmacological activity. They played a major role in the successful medical treatments at ancient times, and their uses have been persevered up to now.1-3 Flavonoid sulfates were found in a large number of plant species. They occupy an important position in the field of natu-ral products chemistry since they provide structures consisted of organic and inorganic components. The pharmacological assay revealed that flavonoid sulfat…  相似文献   

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