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1.
1 INTRODUCTION Halide fluxes are excellent media for growing single crystals of chalcogenides[1~3]. It is well known that during the single crystal growth via flux methods, occasional inclusion of the flux elements in the structure leads to the formation of new phases[4~9]. Several rare earth chalcogenides have been prepared through such reactive halid flux methods[4~9]. Thus we used RbCl as reactive flux to explore a new quaternary selenide by the reaction of ErCuSe precursor with Rb…  相似文献   

2.
SynthesisandCrystalStructureofMnSm_4(SiO_4)_3O¥ChiLi-Sheng;DengShui-Quan;ZhuangHong-Hui;HuangJin-Shun;(StateHeylaboratoryofStr?..  相似文献   

3.
1INTRODUCTIONTheuniqueelectronicpropertiesofcopperoxidesandoxyhalideshaveattractedmuchattentionduetotheirpotentialapplicationsassupercon-ductors,catalysts,luminescentmaterialsandp-typetransparentconductors[1].Inanefforttoexplorenewframeworkstructuresofmixed-metaloxyha-lidessuchasCuAgOCl,wehaveobtainedanewpolymorphofthebariumdicopperdisilicate,b-Ba2CuSi2O7.Inthispaper,wewillreportthesolid-statesynthesisandcrystalstructureofthisnewphaseanddiscussthedifferencesbetweenthestructuresofb-Ba2C…  相似文献   

4.
1INTRoDUCTIONAmongthesilicates,rareearthdisilicatesarespecialbecausetheyshowexten-sivepolymorphism"~".Theconfigurationof(Si,O,)doubletetrahedraisrelativelyrelatedtoperiodicityoftherareearthelectronicstructures,suchasvariationinionicsizeordiscontinuityinchemicalbondingproperties,andalsousefulfordiscussingthedegreeofd-pffbondinginsilicates.SmolinandShepelevhavesynthesizedhightem-peratureformofNd,Si,O,crystallizedinorthorhombicsystem"'.Werecent1yob-tainedlowtemperatureformofNd,Si,O,,which…  相似文献   

5.
顾建明  王林江 《结构化学》1996,15(3):239-242
稀土高氯酸盐开环冠醚三缩乙二醇(EO_3)[La(C_6H_(14)O_4)_3(H_2O)](ClO_4)_3·H_2O,单斜晶系,P2_1/c空间群。晶胞参数为:a=15.474(2),b=11.386(1),c=20.841(4),β=99.82(1)°,V=3618(1),MoKα,Z=4,D_c=1.718g/cm3,μ=1.499mm ̄(-1)。全矩阵最小二乘精细修正,结构因子R=0.056,R_w=0.083。中心原子La与开环冠醚醚链上的O(1)~O(9)及一个水分子形成10配位双帽四方反棱柱结构。弱配体高氯酸根不参加配位。  相似文献   

6.
4-羟基吡啶-2,6-二甲酸铽配合物的制备及其晶体结构   总被引:2,自引:1,他引:2  
以丙酮和草酸二乙酯为原料 ,经过 3步反应合成了 4 羟基吡啶 2 ,6 二甲酸 (HDPA)。HDPA与硝酸铽在水溶液中反应 ,得到标题配合物 ;用X射线衍射法确定其晶体结构 ,分子式为Na3Tb(HDPA) 3·9H2 O ,属三斜晶系P 1空间群 ;晶胞参数 :a =1.10 3 9(5 )nm ,b =1.2 3 83(3 )nm ,c =1.42 5 3 (8)nm ,α =96.10° ,β =10 9.14°,γ =92 .810 (10 )° ,V =1.82 2 9(14 )nm3;Z =2 ;Dc=1.64 4g·cm- 3;μ =2 0 2 1mm- 1 ,R =0 .0 3 74,wR =0 .0 994。配合物较相应配位体吸收带变宽 (2 10~ 3 40nm) ,吸收峰位置出现明显红移 ,而且摩尔吸光系数都有所增加。 4 羟基吡啶 2 ,6 二甲酸铽配合物有很强的黄绿色特征荧光 ,荧光峰 491,5 43 ,5 82 ,62 0nm分别属于 5D4 →7F6 ,5D4 →7F5,5D4 →7F4 ,5D4 →7F3,发射带中最强的是 5D4 →7F5。  相似文献   

7.
SynthesisandCrystalStructureofSquarateComplex[CuLaSm(C_4O_4)_4(H_2O)_(16)]·2H_2O¥ShiJing-Min;YanShi-Ping;LiaoDai-Zheng;JiangZong...  相似文献   

8.
Ernst etal[1 ] reported the synthesis and crystal structure of( 2 ,4 -C7H1 1 ) 3Nd in1 982and then,the crystal structure of( 2 ,4 -C7H1 1 ) 3Gd[2 ] was also determined.In the rareearth triscyclopentadienyl compounds,the Dy complex s structure is not in agreementwith the lanthanide contraction regularity,called“gadolinium break phenomenon”[3] .Inorder to study the reality of this phenomenon,we have determined the crystal structuresof( 2 ,4 -C7H1 1 ) 3Dy( 1 ) and( 2 ,4 -C7H1 1 ) 3Er( 2 ) …  相似文献   

9.
1INTRODUCTIONThesynthesisofpolynuc1earmixedcopper-lanthanoidcomplexesisofinterestforseveralreasons[l-4i.Thesecomplexesareimportanttotheunderstandingofthenature0fthemagneticexchangeinteractionsbetweenrareearthandtransiti0n-metalions,andtheycanpossib1ybeusedasmagneticmaterialst2'33andhightemperaturesuperconductors"'.Itwasbelievedthatthemultidentatepoly-carboxylateacidsisgoodligandsforthepreparationoftheLn-Cumixedmetalcomplexesasthemetalionscanbebridgedbythebidentatecarboxylategroups.Thedig…  相似文献   

10.
以Nd2O3,DMF和α-H6P2W18O62·nH2O等为原料合成了Dawson结构杂多阴离子有机-无机配位聚合物[Nd(DMF)6(H2O)2][Nd(DMF)6(H2O)]P2W18O62,并对其进行了IR,UV光谱表征及电化学性质研究.X-射线衍射单晶结构分析结果表明,晶体属单斜晶系,Cc空间群,晶胞参数a1.8991(3)nm,b=2.2047(3)nm,c=2.6448(4)nm,β=102.272(3)°,并有Z=4,R1=0.043 8,wR2=0.1107.聚合物中存在2种构型的Nd配离子,Nd(1)以九配位的三加冠三棱柱结构通过端氧与[P2W18O62]6-阴离子赤道位的W相连,Nd(2)以九配位畸变的单加冠四方反棱柱结构通过端氧与[P2W18O62]6-阴离子极位的W相连,从而构成分子结构单元[{Nd(DMF)6(H2O)2}{Nd(DMF)6(H2O)}(P2W18O62)],毗邻的结构单元又通过W-O-Nd(1)-O-W桥联形成一维锯齿无限链状结构.  相似文献   

11.
CrystalStructureofPraseodymiumComplexwithL-proline,Pr_2(L-Pro)_6(H_2O)_4·6ClO_4¥WangZeng-Lin;HuNing-Hai;NiuChun-Ji;NiJia-Zuan(C?..  相似文献   

12.
用水热法合成了3,5-二氨基苯甲酸与Nd(Ⅲ)的配合物Nd(C7H7N2O2)3(H2O)3(1),其结构经IR,元素分析和X-射线单晶衍射仪表征。1为单核结构,属六方晶系,R3空间群,晶胞参数:a=1.887 29(18)nm,b=1.887 29(18)nm,c=0.603 53(12)nm,β=90,°γ=120°,V=1.861 7(4)nm3,Z=3,μ=2.154 mm-1,Dc=1.744 g.cm-3,R1=0.014 3,wR2=0.033 2。1中Nd(Ⅲ)与来自3个3,5-二氨基苯甲酸的6个氧原子及3个配位水的氧原子进行配位,形成9配位化合物。  相似文献   

13.
用2-氨基-5-巯基-1,3,4-噻二唑乙酸(Hatma)为配体合成出2种新型同构的稀土配合物[Ln(atma)3(H2O)2]n(Ln=La(1),Nd(2))。配体和2个配合物的结构均由X-射线单晶衍射法确定,同时对配合物进行了IR,TGA及元素分析。单晶结构表明,配体属单斜晶系,C2/c空间群,晶胞参数为a=2.141 9(9)nm,b=0.400 76(17)nm,c=1.750 0(8)nm,V=1.495 0(11)nm3,Z=4;配合物1和2的晶体都属于三斜晶系,空间群为P1,配合物1的晶胞参数为a=0.882 0(3)nm,b=1.230 6(4)nm,c=1.258 6(4)nm,V=1.291 3(7)nm3,Z=2;配合物2的晶胞参数为a=0.883 4(4)nm,b=1.228 3(5)nm,c=1.251 0(5)nm,V=1.282 1(9)nm3,Z=2。2个配合物均形成一维链状空间结构,通过丰富的氢键连接形成三维超分子结构。抗菌试验表明,配合物比配体表现出更好的生物活性。初步的植物生长实验表明,配合物对油菜和小麦的生长具有一定的促进作用。  相似文献   

14.
1 INTRODUCTION The alkali metal chalcogenide halides have at- tracted considerable interests since last decades due to their abundant interesting structures and good properties with potential applications[1~8]. The type of M3QX (M = alkali metal, Q = chalcogenide; X = halide) compounds has been well studied. The known structure types of these compounds are only ternary alkali metal oxide halides and can be classified as the following species: 1) cubic anti-perovskite type, such as K3O…  相似文献   

15.
A 3D infinitely extended structural rare earth coordination compound with a formula of K3{[Sm(H2O)7]2Na[α-SiW11O39Sm(H2O)4]2}·14H2O has been synthesized by reaction of Sm2O3, HClO4, NaOH with α-K8SiW11O39·nH2O, and characterized by IR,UV spectra, ICP, TG-DTA, cyclic voltammetry, variable-temperature magnetic susceptibility and X-ray single-crystal diffraction.X-ray single-crystal diffraction indicates that the title compound crystallizes in a triclinic lattice, Pī space group, with a=1.2462(3) nm, b=1.2652(3) nm,c=1.8420(4) nm,α=87.45(3)°,β=79.91(3)°,γ=82.57(3)°,Z=1, R1=0.0778,wR2=0.1610.Structural analysis reveals that Sm3+(1) coordination cation has incorporated into the vacant site of [α-SiW11O39]8- entity,forming the [α-SiW11O39Sm(H2O)4]5- subunit.The two adjacent [α-SiW11O39Sm(H2O)4]5- subunits are combined with each other through two Sm(1)-O-W bridges accompanying the formation of dimmer structural unit [α-SiW11O39Sm(H2O)4]210- of the title compound.The neighboring dimmer structural units [α-SiW11O39Sm(H2O)4]210- are linked to form the 1D chainlike structure by means of two Sm3+(2) and a Na+(1) coordination cations.The K+(1) cations connect the 1D packing chains constructing the 2D netlike structure, and adjacent netlike layers are also grafted by K+(2) cations to build the novel 3D infinitely extended structure.The result of TG-DTA curves manifests that the decomposition temperature of the title polyanionic framework is 554℃.The cyclic voltammetry measurements show that the title polyanion has the two-step redox processes in aqueous solution with pH=3.1.Variable temperature magnetic susceptibility indicates the title compound obeys the Cruie-Weiss Law in the higher temperature range from 110 to 300 K, while in the lower temperature range from 2 to 110 K the comparatively strong antiferromagnetism interactions can be observed.  相似文献   

16.
A novel one-dimensional chain coordination polymer of terbium(Ⅲ) with p-methylbenzoic acid, 2,2′-bi-pyridine and 4,4′-bipyridine has been synthesized and characterized. The crystal data of this complex C39H37N3O8Tb are as follows: monoclinic system, space group P21/n, a=0.974 01(10) nm, b=2.605 8(3) nm, c=1.457 77(14) nm, β=96.108(2)°, V=3.678 9(6) nm3, Dc=1.507 g·cm-3, Mr=834.64, Z=4, μ(Mo Kα)=1.978 mm-1, F(000)=1 684, R1=0.032 4, wR2=0.063 4. The crystal structure of the complex shows that the terbium(Ⅲ) ion is coordinated with eight oxygen atoms, six from five p-methylbenzoic acid molecules and two from two water molecules, respectively, forming the distorted tetraprism geometry. The luminescent property of the complex is also studied. CCDC: 619216.  相似文献   

17.
The crystal structure of Eu(TFPB)3bpy [TFPB: 4,4,4-trifluoro-1-phenyl-1,3- butanedione, bpy: 2,2′-bipyridyl] has been determined by single crystal X-ray diffraction and the coordination geometry of Eu atom is a square antiprism. The complex can give the characteristic luminescence of Eu3+ upon UV excitation. CCDC: 224879.  相似文献   

18.
Two polymorphs of tripotassium erbium disilicate, K3ErSi2O7, were synthesized by high‐temperature flux crystal growth during the exploration of the flux technique for growing new alkali rare‐earth elements (REE) containing silicates. Their crystal structures were determined by single‐crystal X‐ray diffraction analysis. One of them (denoted 1 ) crystallizes in the space group P63/mmc and is isostructural with disilicates K3LuSi2O7, K3ScSi2O7 and K3YSi2O7, while the other (denoted 2 ) crystallizes in the space group P63/mcm and is isostructural with disilicates K3NdSi2O7, K3REESi2O7 (REE = Gd–Yb), K3YSi2O7, K3(Y0.9Dy0.1)Si2O7 and K3SmSi2O7. In the crystal structure of polymorph 1 , the Er cations are in an almost perfect octahedral coordination, while in the crystal structure of polymorph 2 , part of the Er cations are in a slightly distorted octahedral coordination and the other part are in an ideal trigonal prismatic coordination environment. Sharing six corners, disilicate Si2O7 groups in the crystal structure of polymorph 1 link six ErO6 octahedra, forming a three‐dimensional network and nine‐coordinated potassium cations are located in its holes. In the crystal structure of polymorph 2 , the disilicate Si2O7 groups connect four ErO6 octahedra, as well as one ErO6 trigonal prism. Three differently coordinated potassium cations are situated between them. Different site symmetries of the erbium cations in the crystal structures of polymorphs 1 and 2 affect their photoluminescence properties. Only polymorph 2 exhibits luminescence. Intense narrow lines in the emission spectrum are a result of the 4f–4f transition. The green emission line at 560 nm is the result of the Er3+ transition 4S3/24I15/2, and the luminescence line at 690 nm is the result of a 4F9/24I15/2 transition. The crystal morphologies of the two polymorphs are similar. Crystals of polymorph 1 are in the form of a hexagonal prism in combination with a hexagonal base, while crystals of polymorph 2 contain a dihexagonal prism in combination with a hexagonal base, although poorly developed faces of the dihexagonal pyramid can also be noticed.  相似文献   

19.
(C5H4CH3)3Ho和(C5H4CH3)2Ho(C5H5)与5-苯基四唑(HN4CPh)在THF中反应,得到复合产物[(C5H4CH3)2HoN4CPh]2·[(C5H4CH3)(C5H5)HoN4CPh]2,该晶体属三斜晶系,P1空间群,晶胞参数为a=9.386(3),b=13.071(3),c=16.571(2)A,a=86.90(1),β=74.61(2),γ=77.30(2)°,V=1912.2(8)A3,Z=1,Dc=1.602g/cm3,Mr=922.61,μ=41.92cm-1,F(000)=896,最终偏离因子R=0.041,Rw=0.056.晶体数据显示,在同一个晶胞里有两个组成不同的分子,每一个分子都是具有对称中心的四唑基桥二聚体结构,其桥环单元-HoN3HoN3-是平面型的。每个钬原子分别被两个茂基和3个四唑基氮原子配位,形成1个边桥变形四面体构型。  相似文献   

20.
1 INTRODUCTION At present the researches on more efficient solid-state laser materials become more important for the rapid development of diode-laser pumped solid-state laser. More researches have been devoted to the double borate compounds RX3(BO3)4 (R = Y, La, Gd and X = Y, Al, Sc), some of which exhibit good chemical and physical properties[1~10]. The rare earth and alkali-halide double borates M3Ln2(BO3)4 (M = Ca, Sr, Ba and Ln = LaLu and Y) were reported in literatures[11…  相似文献   

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