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1.
The hydrothermal reaction of MoO3, V, Na2WO4· 2H2O, [N(CH2CH2)3N](1,4-diazabicyclo[2.2.2] octane), and H2O at 160°C for 90h gave dark-brown crystals of [HN(CH2CH2)3N]2[HMoVMoVI 5O19]·[N(CH2CH2)3N], (1), in 40% yield. Complex (1) is the first one-electron reduced mixed-valence hexamolybdate to be crystallized and structurally characterized. The crystal structure of (1) consists of discrete [HMoVMoVI 5O19]2– anions, [HN-(CH2CH2)3N]+ cations, and neutral [N(CH2CH2)3N] molecules of crystallization.  相似文献   

2.
Using ESR and IR spectroscopy, the structures of >Si(O–C·=O)(CH2–CH3) (1) and >Si(CH2–CH·–CH3)(CH2–CH3) (2) radicals were deciphered. The directions and kinetic parameters of reactions of intramolecular rearrangements in these radicals were determined. The reactions of hydrogen atom abstraction in radical (1) from the CH2 and CH3 groups were studied. It was found that the endothermic reaction of hydrogen atom abstraction from the methyl group occurs at a higher rate than the exothermic reaction with the methylene group. The differences are determined by changes in the size of a cyclic transition state. Based on the experimental data, the strengths of separate C–H bonds in surface fragments are compared. The rearrangement >Si(CH2–CH·–CH3)(CH2–CH3) >Si(C·(CH3)2)(CH2–CH3) was discovered and its mechanism was determined. One of its steps is the skeletal isomerization Si- (2)- . (1)Si- (1)- . (2). Experimental data are analyzed using the results of quantum-chemical calculations of model systems.  相似文献   

3.
[(CH3)2NH2]3[NSiMo12O40]·2DMF·4H2O的合成和晶体结构   总被引:5,自引:0,他引:5  
电荷转移盐;[(CH3)2NH2]3[NSiMo12O40]·2DMF·4H2O的合成和晶体结构  相似文献   

4.
Crystals of [Cr3O(CH3COO)6(H2O)3][UO2(CH3COO)3]·3H2O (I) were synthesized for the first time and studied by X-ray crystallography. The crystals of I are orthorhombic: a = 8.3561(3) ?, b = 16.8421(5) ?, c = 25.7448(9) ?, V = 3623.2(2) ?3, space group P212121, Z = 4, R = 0.0409. The structure is composed of trinuclear [Cr3O(CH3COO)6(H2O)3]+ complexes and mononuclear [UO2(CH3COO)3]? complexes classified with crystal-chemical groups A3M3B 6 2 M 3 1 (A = Cr3+, M3 = O2?, B2 = CH3COO?, M1 = H2O) and AB 3 01 (A = UO 2 2+ , B01 = CH3COO?), respectively. The complexes are bound to each other by electrostatic interactions and hydrogen bonds involving outer-sphere water molecules. The results of IR spectroscopic study of I are in good agreement with the structural data for the crystal.  相似文献   

5.
无机-有机杂化钒氧酸盐由于其结构的多样性以及在催化、医药、光、电、磁等材料领域中的应用前景而受到人们的广泛关注。近年来这一研究领域的重大进步是将有机氮配体或者过渡金属配合物直接连接到矾氧骨架上以获得各种新奇结构。合成出许多属于L/V/O、MXLY/V/O、L/P/V/O和MXLY  相似文献   

6.
After a short survey of what is the present state of the cyclophosphates associated with the organic molecule NH2(CH2)4NH2, we report chemical preparation and crystal structure for a new example of such compounds. [NH3(CH2)4NH3]2P4O12.2H2O is monoclinic (S.G. : P21/n), with Z = 2 and the following unit-cell parameters : a = 7.6728(8) Å, b = 18.962(3) Å, c = 7.9789(9) Å β = 111.751(9)°. Bidimensional layer arrangement of P4O12 rings connected to the water molecules thanks to weak H-bonds run parallel to the ab plane. The organic groupements located between these inorganic planes perform the three-dimensional cohesion by NH····O hydrogen bonds.  相似文献   

7.
同多化合物[C6H5CH2NH(CH3)2]4[Mo8O26]·4H2O的合成与晶体结构   总被引:2,自引:2,他引:0  
以MoO3和C6H5CH2N(CH3)2为原料,制得[C6H5CH2NH(CH3)2]4[Mo8O26]·4H2O,并通过扩散法得到无色透明晶体.X射线单晶衍射表明,晶体属三斜晶系,空间群为P墿,晶胞参数a=1.0685(2)nm,b=1.4050(3)nm,c=1.0643(2)nm,α=93.12(3)°,β=110.26(3)°,γ=71.41(3)°,V=1.4179(5)nm3,R=0.0383.  相似文献   

8.
The synthesis and crystal structures of [H3NCH2CH2NH3][V2O6] (1) and [HN(CH2CH2)3NH][VV 2VIV 4O14]·H2O (2) are described. The structure of the oxidized compound 1 consists of parallel stacks of vanadium oxide chains of corner sharing {VO4} tetrahedra. The chains are stabilized by extensive hydrogen bonding involving oxide ligands of the chains and ethylenediammonium ions which fill the space between the stacks of chains. The structure of compound 2 consists of vanadium oxide layers separated by doubly protonated 1,4-diazabicyclo[2.2.2]octane and lattice water. The vanadium oxide layers, containing mixed-valence vanadium (VV and VIV) centers, are composed of zigzag ribbons of edge-sharing {VO5} square pyramids interconnected by {VO4} tetrahedra. Crystal data. C2H10N2O6V2 , 1: monoclinic, space group P21/c (No. 14), a=5.5359(5), b=12.9430(12), c=5.6856(5) Å, =90, =97.460(2), =90°, V=403.93(6) Å3, Z=2. A total of 2506 reflections ( max=27.89°) was collected, of which 954 were used to resolve the structure. The structure was solved by direct methods and least-squares refinement converged at R=0.0592. C6H16N2O15V6, 2: monoclinic, space group C2 (No. 5), a=19.303(4), b=6.667(2), c=7.579(2) Å, =90, =111.31(2), =90°, V=908.4(4) Å3, Z=2. A total of 1779 reflections was collected, of which 1591 unique reflections were used for structural elucidation. The structure was solved by direct methods and least-squares refinement converged at R=0.0314.  相似文献   

9.
The reaction of Sn[CH(SiMe3)2]2 and ethyne at ambient temperature affords a mixture of products, from which the title compound has been separated and identified by IR, 1H, and 13C NMR spectroscopy.  相似文献   

10.
<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   

11.
The heteronuclear-oxoacetate with the composition [Fe2NiO(CH2COO)6(H2O)3]·2H2O decomposed on heating, forming nickel ferrite NiFe2O4 and (depending on the decomposition conditions) in part other solid phases. H2O, CH3COOH, acetone and CO2 were also formed in the decomposition. A reaction scheme is given for the decomposition. The products were porous powders with grain diameters between 3 and 10m. On increase of the temperature of decomposition from 300 to 800 C, the BET surface area and the surface area of the pores decreased, but only a small alteration in grain size was observed. As a result of thermal treatment in the temperature region abone 800C, larger aggregates of grains were formed in sintering processes.
Zusammenfassung Heteronukleare-Oxoazetate der Zusammensetzung [Fe2NiO(CH3COO)6(H2O)3]·2H2O werden durch Erhitzen zersetzt, wobei Nickelferrite NiFe2O4 und — in AbhÄngigkeit von den Bedingungen der Zersetzung — mit einem Teil anderer fester Phasen gebildet wird. In der Zersetzungsreaktion werden auch H2O, CH3COOH, Azeton und CO2 gebildet. Es wird ein Reaktionsschema für die Zersetzung angegeben. Die Produkte sind poröse Pulver mit einem Korndurchmesser zwischen 3 und 10 m. Wird die Zersetzungstemperatur von 300 auf 800C erhöht, nimmt die BET-OberflÄche und die PorenoberflÄche ab, wobei sich die Korngrö\e aber nur wenig verÄndert. Im Ergebnis der WÄrmebehandlung im Temperaturbereich oberhalb 800C werden durch Sinterprozesse grö\ere Partikelaggregate gebildet.
  相似文献   

12.
杂多金属氧酸盐;钨硅酸;二乙醇胺;[(HOCH2CH2)2NH2]8·[SiW12O40]2·H2O的合成、表征、晶体结构及性质  相似文献   

13.
The synthesis of 1,5-bis(2-dihydroxyphosphoryl-4-ethylphenoxy)-3-oxapentane [(HO)2(O)P(C6H3CH2CH3)(OCH2CH2)2O(C6H3CH2CH3)P(O)(OH)2] (H4K2) and single crystal X-ray diffraction study of H4K2 · 2H2O (I) are described. The crystals are orthorhombic, a = 33.291(4) Å, b = 8.9374(10) Å, c = 8.1021(9) Å, V = 2410.6(5) Å3, Z = 4, space group Cmc21, R = 0.0484 for 2566 reflections with I > 2σ(I). In I, the molecules of H4K2 are hydrogen-bonded to two crystallographically independent H2O molecules to give neutral conglomerates H4K2 · 2H2O. The electroanalytical characteristics of poly(vinyl chloride) membranes based on H4K2 were tested. Cu2+ and Zn2+ complexes with H4K2 and Er3+, Nd3+, and complexes with H4K2, 1,5-bis[2-(dihydroxyphosphoryl-4-methoxy)phenoxy]-3-oxapentane, 1,5-bis[2-(dihydroxyphosphinyl)phenoxy]-3-oxapentane, and 1,8-bis[2-(dihydroxyphosphinyl)phenoxy]-3,6-dioxaoctane were prepared.  相似文献   

14.
Single crystals of (NH4)2[(UO2)2C2O4(CH3COO)4] · 2H2O have been synthesized and studied. The compound crystallizes in the orthorhombic system with the unit cell parameters a = 6.9225(14) Å, b = 12.327(3) Å, c = 14.619(3) Å, space group Immm, Z = 2, and V = 1247.6(5) Å3. The main structural units of the crystals are the isle binuclear groups [(UO2)2C2O4(CH3COO)4]2? belonging to the crystal-chemical group A2K02B 4 01 (A = UO 2 2+ , K02 = C2O 4 2? , B01 = CH3COO?) of the uranyl complexes. The uranium-containing groups are linked into a three-dimensional framework due to electrostatic interaction with the ammonium cations and through a system of hydrogen bonds involving atoms of the water molecules, oxalate and acetate ions, and ammonium and uranyl cations.  相似文献   

15.
The title compound has been synthesized by the reaction of HgI2 and [(CH3)3- NCH2CH2N(CH3)3]I2 with pH = 7.5 at room temperature, and its crystal structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group P21/c with a = 8.3075(8), b =15.8084(19), c =15.390(2)(°A), β = 95.192(4)o, V = 2012.9(4)(°A)3, Z = 2, Dc = 2.824 g/cm3, F(000) = 1502, C14H39N4O2Hg2I8, Mr = 1711.87, μ(MoKα) = 13.768 mm-1, the final R = 0.0465 and wR = 0.1293 for 3046 observed reflections with I > 2(I). The title compound consists of cations ([C8H22N2]2+) and anion (HgI42-), which are combined by static attracting forces to form the so-called organic-inorganic hybrid material.  相似文献   

16.
The supramolecular complex [Zn{NH(CH2)4O}{S2CN(C2H5)2}2]2 · CH2N(CH2)4O}2 (I) has been synthesized and studied by X-ray crystallography and thermal analysis. The noncentrosymmetric complex is composed of two structurally nonequivalent molecules of the adduct of bis(diethyldithiocarbamato)zinc with morpholine, which are linked with the outer-sphere N,N’-dimorpholinomethane molecule through two hydrogen bonds N-H?O. The major differences between the adduct molecules are related to the strength of Zn-N bonds, spatial orientation of the coordinated morpholine heterocyclic rings, and the proportion between the contributions of the trigonal bipyramidal (TBP) and tetragonal pyramidal (TP) components to the geometry of zinc polyhedra. Calculations show that the geometry of the zinc polyhedra is almost halfway between TBP and TP. The thermal destruction of supramolecular compound I is accompanied by desorption of the outer-sphere and coordinated organic molecules. At the final stage, defragmentation of the “dithiocarbamate part” of the complex leads to the formation of ZnS.  相似文献   

17.
合成了砷钼夹心型化合物Na5[ (CH3)4N]3( H3O)2[ Co2( AsVMo9O33)2]·8H2O,用X-射线单晶衍射、元素分析和红外光谱对晶体的结构进行了表征.结构表征指出该化合物是由砷钼夹心型[ Co2(AsVMo9O33)2]10-多阴离子,( CH3 )4N+反荷阳离子,Na+反荷阳离子和结晶水分...  相似文献   

18.
《Solid State Sciences》2012,14(5):611-615
Three new ionic crystals based on Keggin anion and mixed-valent diruthenium tetracetate, [Ru2(CH3CO2)4(H2O)2]2[HnXW12O40]·[Ru2(CH3CO2)4(H2O)Cl]·12H2O {X = B, n = 3 (1); X = Si, n = 2 (2); X = Ge, n = 2 (3)}, have been prepared in acidic aqueous solution at about pH 3.0 by reaction of K4BW12O40·mH2O, K8SiW11O39·mH2O and K8GeW11O39·mH2O with diruthenium tetracetate Ru2(CH3COO)4Cl, respectively, and their structures were determined by X-Ray diffraction analysis. They are isostructural structure with the ratio of heteropolytungstate anion, Ru2(CH3CO2)4+ cation and neutral molecular Ru2(CH3CO2)4Cl of 1:2:1. The cyclic voltammetry in 0.5 M KNO3 aqueous solution at pH 3.0 show the respective electrochemical behaviors of the W-centers and Ru2-centers for these three complexes. Magnetic data analysis shows that diruthenium units display the ground state electronic configuration π*2δ* with large positive D value.  相似文献   

19.
杀虫单(CH3)2NHCH(CH2S2O3)2Na·H2O是我国独自开发的一种沙蚕毒系仿生性农药.我们用循环伏安法和计时库仑法研究了杀虫单的电极反应过程及在电位扫描速率,支持电解质PH以及浓度变化时对峰电流及峰电位的影响.研究表明杀虫单发生不可逆还原电极反应,还原产物二氢沙蚕毒素在电极上发生强吸附,其吸附量为8.23×10-10mol/cm2.在随后的循环电位扫描中二氢沙蚕毒素氧化生成沙蚕毒素在循环伏安图上出现新电流峰.沙蚕毒素与二氢沙蚕素的峰电位相差33mV,两者间有2电子可逆电极反应特征  相似文献   

20.
Cs3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) and Cs5[UO2(CH3COO)3]3[UO2 (NCS)4(H2O)] · 2H2O (II) have been synthesized via the reaction between uranyl acetate and cesium thiocyanate in aqueous solution. According to single-crystal X-ray diffraction data, both compounds crystallize in monoclinic system with the unit cell parameters a = 18.7036(5) Å, b = 16.7787(3) Å, c = 12.9636(3) Å, β = 92.532(1)°, space group C2/c, Z = 4, R = 0.0434 (I); and a = 21.7843(3) Å, b = 24.6436(5) Å, c = 13.1942(2) Å, β = 126.482(1)°, space group Cc, Z = 4, R = 0.0273 (II). Uranium-containing structural units of compound (I) are mononuclear [UO2(CH3COO)3]? and [UO2(CH3COO)(NCS)2(H2O)]? moieties, which correspond to the AB 3 01 and AB01M 3 1 crystallochemical groups (A = UO 2 2+ , B01 = CH3COO?, M1 = NCS? and H2O). The structure of compound II is built of [UO2(CH3COO)3]? and [UO2(NCS)4(H2O)]2? complexes, which belong to the AB 3 01 and AM 5 1 crystallochemical groups, respectively. Uranium-containing complexes in both structures are linked into a framework by hydrogen bonds and electrostatic interactions with cesium cations. The IR spectra of compounds I and II agree well with X-ray diffraction data.  相似文献   

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