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1.
许章林  张盈珍 《分子催化》1992,6(5):365-370
分别以NH_4Y及ZSM-5为原料,(NH_4)_2TiF_6、(NH_4)_3FeF_6为取代剂,进行液-固相类质同晶取代反应,并用XRD、IR、ESR、M(?)ssbauer谱等一系列方法进行了表征,结果发现:Ti进入了Y型及ZSM-S沸石骨架;Fe只进入了Y型沸石骨架,而没能进入ZSM-5沸石骨架,Fe、Ti杂原子进入沸石后,其晶胞参数增大,红外对称和反对称伸缩振动的频率向低频移动。  相似文献   

2.
金属元素对Y沸石的液固相类质同晶取代   总被引:3,自引:0,他引:3  
用(NH_4)_2TiF_6、(NH_4)_3ZrF_7和(NH_4)_3FeF_6为取代剂研究了Ti、Pe和Zr等杂原子对Y沸石的液固相类质同晶取代规律,发现Ti、Fe和Zr主要取代Y沸石中的A1,其取代程度取决于溶液中M/A1比,最高允许M/A1比与杂原子的半径和氟配合物的稳定常数有关。用XRD、IR、DTA和TPR表征了相对结晶度大于80%的杂原子Y沸石。Ti、Fe和Zr等杂原子进入Y沸石后,沸石的晶胞参数增大,热稳定性下降,红外反对称伸缩振动频率红移,且变化的程度与取代原子的半径和取代量有明显的对应关系,说明杂原子以四面体形式进入Y沸石骨架。  相似文献   

3.
陈延民  王树涛  王恩波 《化学学报》2002,60(11):1999-2003
化合物(NH_4)_2GeF_6·H_2O由GeO_2,NH_4VO_3和HF在吡啶-水体系中低温溶剂 热条件下合成,并用IR、元素分析、TG-DTA和X射线单晶衍射进行了表征。化合物 属立方晶系,空间群为Fm3m, a=0.9118(2)nm,β=90°,V=0.7580(3)nm~3,Z=1, D_c=2.021g/cm~3,F(000)=432,R_1=0.0612, wR_2=0.1510。晶体结构中包含4个 GeF_6,4个H_2O和8个孤立的NH_4~+离子。其中晶格水的引入导致了GeF_6~(2-)八面 体为O_h对称性;进而GeF_6和H_2O通过强烈的F…H-O氢键链接成-3D具有0. 6559nm*0.6559nm*0.6559nm空腔的栅格状骨架的超分子(NH_4)_2GeF_6·H_2O化合 物。NH_4~+位于栅格的中心,以静电引力与GeF_6~(2-)作用,进一步稳定了3D超分 子网络。  相似文献   

4.
从(NH_4)_2MoS_4或(NH_4)_2WS_4,FeCl_2,R_2NCS_2NH_4(或其钠盐)起始,在DMF中经自兜反应制得了MoFes_3S4(R_2NCS_2)_5(R_2=—(CH_2)_4—,Bz_2)及WFe_3S_4(R_2NCS_2)_5(R_2=Me_2,—(CH_2)_4—)两种单立方烷原子簇。前者也可从链状簇合物Fe(DMF)_6[(FeCl_2)_2MoS_4]转化而生成。MoFe_3S_4(C_4H_8NCS_2)_5及WFe_3S_4(C_4H_8NCS_2)_5结构相似,单胞参数几乎相同。在比较它们结构基础上,讨论了这一系列单立方烷原子簇的结构特点,对它们的红外,顺磁谱及电化学性质也进行了研究。  相似文献   

5.
应用倒滴加法制备的粉状白钨酸,制备了两个新的不同组成的过氧钨酸钕:NH_4NdW_2(O_2)_5(OH)_2·4H_2O(1)和NH_4NdW_3(O_2)_3O_8·6H_2O(2)并对化合物的一些性质进行了表征。  相似文献   

6.
通过溶剂热技术,制得一种新型的Cd~(2+)配合物[Cd(L)_2(ba)_2]_2(1,L=4'-(4-甲基苯)-4,2':6',4″-三联吡啶,Hba=苯甲酸),其结构经IR,元素分析和单晶射线衍射表征。1属单斜晶系,空间群为P2_1/c,晶胞参数a=1.095 5(2)nm,b=1.404 1(3)nm,c=3.045 5(8)nm,β=103.37(3)°,V=4 557.6(18)3,D_c=1.459g·cm~(-3),Z=2,R_1=0.045 5,wR_2=0.094 0[I2σ(I)]。结构分析表明:1为零维双核结构,通过π…π堆积作用拓展为二维层状超分子。  相似文献   

7.
咪唑桥联异三核配合物[(NH_3)_5CoImCu(dien)ImCo(NH_3)_5]·(ClO_4)_6·4H_2O和[(NH_3)_5CeImZn(dien)ImCo(NH_3)_5](ClO_4)_6·4H_2O均属单斜晶系C2/C空间群,前者a=33.414(4),b=9.421(1),c=15.167(5),β=90.91(2)°,Z=4;后者a=32.578(2),b=9.419(1),c=15.125(3),β=91.10(1)°,Z=4。两种分子中Cu,Zn离子的构型均介于四方锥和三角双锥间,但更接近四方锥构型。Cu,Zn周围二乙烯三胺配体存在着无序分布,使混合单晶的ESR谱中出现两套Cu(Ⅱ)信号。应用适于求非同轴g和A张量的最小二乘方拟合技术,解出Co—Cu—Co配合物的两套g张量和A张量主值及其主轴的方向余弦,并计算了配合物中Cu(Ⅱ)上的电子自旋密度分布。  相似文献   

8.
将闭式+氢+硼酸阴离子酰胺衍生物[B_(10)H_9NH_2COCH=CH_2]~-、双苯甲酰丙酮缩1,3-丙二胺C_6H_5C(OH)=CHC(CH_3)=N(CH_3)CH=C(OH)C_6H_5(Bapn)及希土氯化物在丙酮-乙醇混合溶剂中进行反应,得到分子式为Ln(Bapn)_3[B_(10)H_9NH_2COCH=CH_2]_3(Ln=La,Nd,Sm,Eu,Gd,Dy)的混式配体希土配合物。通过元素分析、IR、~1H NMR及摩尔电导率的测定对配合物进行了表征,还通过DTA-TG方法研究了它们的热性质。  相似文献   

9.
The structures of the heterotrinuclear complexes, [(NH_3)_5ColmCu(dien)ImCo(NH_3)_5]-(C10_4)_6·4H_20 and [(NH_3)_5CoImZn(dien)ImCo(NH_3)_5]-(ClO_4)_6·4H_2O, are reported. Co--Cu--Cocrystallizes in the monoclinic space group C2/c with a =32.414(4), b= 9.421(1), c=15.167(5)?,β= 90.91(2)°, Z=4 and Co--Zn--Co in the same space group with a = 32.578(2), b = 9.419(1), c = 15.125(3)?, β=91.10(1)°Z=4. The Cu(Ⅱ) and Zn(Ⅱ) geometriesare intermediate between a trigonal bipyramid and a square pyramid,the Co(Ⅲ) is a-hexagonal coordination and the dien ligand shows a disordered contribution in the respectivestructure.The magnetic properties of Co--Cu--Co are investigated. From the single crystalESR spectra studies, the anisotropic g and A tensors and electronic spin-density of Co--Cu--Co are obtained and the nature of the bonding for Cu~(2+) is discussed.  相似文献   

10.
利用磷钼十二酸、偏钒酸铵、CuCl_2·2H_2O和3,3′,5,5′-四甲基-4,4′-联邻二氮杂茂(H_2X)在水热条件下反应,合成出了1个新的多酸基杂化化合物Cu_4(H_2X)_4[(PMo_(12)O_(40)(VO)_(0.5))].通过X射线单晶衍射、红外光谱和热重分析等测试手段对该化合物进行了结构表征.单晶结构解析表明该化合物为2D层状化合物,属于单斜晶系,C2/c空间群,晶胞参数a=2.637 6(5)nm,b=1.542 2(5)nm,c=2.057 0(5)nm,α=90.000(5)°,β=112.677(5)°,γ=90.000(5)°,V=7.720(3)nm~3,Z=4,R_1=0.061 5,wR_2=0.164 6.  相似文献   

11.
Behera JN  Rao CN 《Inorganic chemistry》2006,45(23):9475-9479
An organically templated iron(II) sulfate of the composition [H3N(CH2)2NH2(CH2)2(NH3]4[Fe(II)9F18(SO4)6].9H2O with a distorted Kagome structure has been synthesized under solvothermal conditions in the presence of diethylenetriamine. The distortion of the hexagonal bronze structure comes from the presence of two different types of connectivity between the FeF4O2 octahedra and the sulfate tetrahedra. This compound exhibits magnetic properties different from those of an Fe(II) compound with a perfect Kagome structure and is a canted antiferromagnet at low temperatures.  相似文献   

12.
设计合成了2个一维链状铬酸根桥连的配位聚合物(NH4)2[Cu(NH3)2(CrO4)2](1)和(NH4)2·[Ni(NH3)2(CrO4)2](2), 并对其进行了X射线单晶结构分析、 热重-差热分析和多种磁学测试. 晶体结构分析表明, 2个配合物的晶体均属于三斜晶系, 空间群均为P1. 配合物1的晶胞参数为: a=0.59090(12)nm, b=0.6929(3) nm, c=0.73740(15) nm, α=107.03(4)°, β=92.79(3)°, γ=112.44(2)°; 配合物2的晶胞参数为: a=0.56987(7)nm, b=0.69972(9) nm, c=0.73335(8)nm, α=104.929(3)°, β=96.121(3)°, γ=112.325(4)°. 热重分析结果表明, 配合物1和2均在150 ℃左右开始分解, 生成H2Cr2CuO5和H2Cr2NiO5, 在410 ℃以上继续分解, 脱水得到相应的氧化物. 配合物的变温磁化率测试结果表明, 相邻Cu(Ⅱ)离子(配合物1)或Ni(Ⅱ)离子(配合物2)之间存在较弱的反铁磁相互作用; 低温变场和交流磁化率测试结果表明, 2个配合物均为反铁磁体.  相似文献   

13.
杂原子对Y沸石液固相类质同晶取代规律探讨   总被引:1,自引:0,他引:1  
高滋  徐金锁 《化学学报》1995,53(2):135-140
用NH~4BF~4,(NH~4)~3ZrF~7,(NH~4)~2Tif~6,(NH~4)~3FeF~6和CrF~3,3NH~4F等溶液为取代剂,对Y沸石实行液固相类质同晶取代,除了B以外, 其它金属元素均能代入沸石骨架,它们的取代程度为Fe>Ti>Cr≈Zr.采用XRD,IR和DTA 等手段对取代产物进行表征,证实杂原子已成为骨架元素.由液固相类质同晶取代机理出发, 对影响杂原子取代程度的主要因素进行了探讨,提出由杂原子的离子半径.含氟配合物累积稳定常数. 阳离子水解平衡常数和水解产物聚合平衡常数可以预测各种杂原子的取代效果.  相似文献   

14.
The substitutions of Ti, Fe and Zr into zeolite Y in the aqueous solutions of (NH4)2TiF6, (NH4)3ZrF7 and (NH4)3FeF6 were systematically Investigated. It was found that Ai atoms in the framework can be replaced by some metallic elements and the extent of substitution depends on the M/A1 ratio of the solution. The maximum allowable M/A1 ratio of the aqueous solution Is related with the radius of the M atom and the stability constant of the MFnm- complex. The substituted zeolite samples with crystallinity greater than 80% were characterized by means of XRD, IR, DTA, TPR and NH3-TPD measurements. The incorporation of Ti, Fe and Zr into the zeolite leads to an increase in the unit cell parameter, a lowering of thermal stability and a red shift of the asymmetric stretching frequency. The extent of these changes is apparently related with the ionic radius of the metallic element and the degree of substitution. The results of various characterization methods show that the het-eroatoms are readily Introduced int  相似文献   

15.
Salts of the monooxomolybdenum(IV,V) areneselenolates having intramolecular NH...Se hydrogen bonds, [Mo(IV)O(Se-2-RCONHC6H4)4]2- (R = t-Bu, CH3, CF3) and [Mo(V)O(Se-2-t-BuCONHC6H4)4]-, were synthesized and characterized by 1H nuclear magnetic resonance (NMR), 77Se NMR, electron spin resonance (ESR), UV-visible spectra, X-ray analysis, and electrochemical measurements. 77Se-1H correlated spectroscopy (COSY) indicated a significant correlation between amide 1H and selenolate 77Se atoms through an NH...Se hydrogen bond with 1J(77Se-1H) = 5.4 Hz coupling. The hydrogen bonds contribute to the positive shift in the Mo(V)/Mo(IV) redox potential. In the crystal structure of (PPh4)2[Mo(IV)O(Se-2-CH3CONHC6H4)4], an NH...O=Mo hydrogen bond was found. Ab inito calculations support the presence of intramolecular NH...O=Mo and NH...Se hydrogen bonds.  相似文献   

16.
A new three-dimensional open-framework cobalt(Ⅱ)-tungsten(Ⅵ) phosphate,[H3NCH2CH2NH3]3·[Co3W4P4O28](1) has been synthesized from the reaction of CoCl2·6H2O,WO3,H3PO4,ethylenediamine and H2O.The title compound was fully characterized by infrared spectroscopy,elemental analysis,magnetic properties,thermogravimetric analysis,XPS and single-crystal X-ray diffraction.The compound crystallized in a tetragonal space group I4(1)/a with a=1.7118(4) nm,c=1.0773(2) nm,V =3.1568(11) nm3,Z =4.  相似文献   

17.
通过助剂掺杂的方法解决MgF2催化剂高温失活的问题。采用溶胶-凝胶法制备了一系列Fe^3+掺杂的高比表面MgF2催化剂,并通过N2吸附-脱附测试、X射线衍射(XRD)、能量色散X射线光谱(EDS)和NH3程序升温脱附技术(NH3-TPD)、电子自旋共振(ESR)、X射线光电子能谱(XPS)等对FeF3/MgF2催化剂的物化性质进行了表征。结果表明,一定量(物质的量分数小于20%)的Fe^3+掺杂可以有效地减少MgF2晶粒度,且随着Fe^3+掺杂量的增加,催化剂的比表面积、酸性及1,1-二氟乙烷(R152a,C2H4F2)脱HF反应的催化活性均呈现增加趋势,但当Fe^3+掺杂量超过20%时,催化剂明显失活。  相似文献   

18.
The novel gadolinium(III) containing compounds (CH3NH3)2[Gd2(CCl3COO)6(H2O)6](CCl3COO)2.2CCl3COOH (1) and (NH3CH3)2[Gd4(OH)4(CCl3COO)10(H2O)6].2H2O (2) were synthesized and structurally characterized by X-ray crystallography. In the crystal structure of 1 the gadolinium ions are bridged by carboxylate groups to dimers with a Gd3+ -Gd3+ distance of 420.2(3) pm. The compound crystallizes in the triclinic space group P1. In the crystal structure of the Gd3+ ions are bridged by hydroxide ions and carboxylate groups to tetramers with Gd3+ -Gd3+ distances between 380.3(1) and 388.0(1) pm. The compound crystallizes in the triclinic space group P1. The magnetic behaviour of these two compounds as well as of Gd2(CCl3COO)6(bipy)2(H2O)2.4bipy (3) (bipy = 2,2'-bipyridyl) was investigated in the temperature range 1.77-300 K. The magnetic data for these compounds indicate weak antiferromagnetic interactions.  相似文献   

19.
We report the synthesis of spin crossover 69 nm spherical nanoparticles of [Fe(NH(2)-trz)(3)](Br)(2).3H(2)O.0.03(surfactant) (NH(2)trz = 4-amino-1,2,4-triazole, surfactant = Lauropal), prepared by the reverse micelle technique, which exhibit at room temperature a thermal hysteresis characterized by magnetic, diffuse reflectivity and Raman studies.  相似文献   

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