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1.
Molecular beam deflection studies on (CO2)2 and (OCS)2 indicate that both these species are polar molecules. Structural implications of this are explored in light of previous studies of these systems.  相似文献   

2.
Infrared and Raman spectra on Na3H(SO4)2, K3 H(SO4)2 and (NH4)3 H(SO4)2 crystals have been investigated at 300 and 100 K in the 4000 to 30 cm−1 region. An assignment of bands in terms of OH group frequencies and more or less distorted tetrahedra of ammonium and sulphate ions is given. The crystallographic and spectroscopic symmetry and/or dissymetry of OHO hydrogen bonds linking sulphate ions into dimers is discussed using OH group frequencies and the splitting of the v1 (SO4) Raman bands as criteria. In the particular case of (NH4)3H(SO4)1 compound containing several solid phases it can be shown that the room temperature phase (II) is strongly disordered, principally because of an orientational disorder of ammonium ions, and that a progressive ordering takes place with temperature lowering.  相似文献   

3.
Crystal structures of Pb(MoO2)2(PO4)2 and Ba(MoO2)2(PO4)2 were determined. Both compounds contain the molybdyl group MoO2. The monoclinic unit-cell parameters are a = 6.353(7), b = 12.289(4), c = 11.800 Å, β = 92°56(6), and Z = 4 for the lead salt and a = 6.383(8), b = 7.142(7), c = 9.953(8) Å, β = 95°46(8), and Z = 2 for the barium salt. P21c is the common space group. The R values are respectively R = 0.027 and R = 0.031 for 1964 and 1714 independent reflections. The frameworks built up by a three-dimensional network of monophosphate PO4 and molybdyl MoO2 groups are similar, characterized mainly by corner-sharing PO4 and MoO6 polyhedra. Two oxygen atoms of each MoO6 group are bonded to the molybdenum atom only as in other molybdyl salts.  相似文献   

4.
Phase equilibria in the Ba3(VO4)2-K2Ba(MoO4)2 and Pb3(VO4)2-K2Pb(MoO4)2 systems have been investigated. In the first system, a continuous series of substitutional solid solutions with the palmierite structure is formed, and in the second one, the polymorphic transition in lead orthovanadate at 100°C restricts the extent of the palmierite-type solid solution to 10–100 mol % K2Pb(MoO4)2. Original Russian Text ? V.D. Zhuravlev, Yu.A. Velikodnyi, A.S. Vinogradova-Zhabrova, A.P. Tyutyunnik, V.G. Zubkov, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 10, pp. 1746–1748.  相似文献   

5.
Raman and FTIR spectra of guanidinium zinc sulphate [C(NH2)3]2Zn(SO4)2 are recorded and the spectral bands assignment is carried out in terms of the fundamental modes of vibration of the guanidinium cations and sulphate anions. The analysis of the spectrum reveals distorted SO42− tetrahedra with distinct S–O bonds. The distortion of the sulphate tetrahedra is attributed to Zn–O–S–O–Zn bridging in the structure as well as hydrogen bonding. The CN3 group is planar which is expressed in the twofold symmetry along the C–N (1) vector. Spectral studies also reveal the presence of hydrogen bonds in the sample. The vibrational frequencies of [C(NH2)3]2 and HC(NH2)3 are computed using Gaussian 03 with HF/6-31G* as basis set.  相似文献   

6.
Phase diagrams of the systems K2SO4Sc2(SO4)3, Rb2SO 4Sc2(SO4)3 and Cs2SO4 Sc2(SO4)3 have been investigated by X-ray diffraction phase analysis and differential thermal analysis techniques. A salient feature of all the systems is the formation of M3Sc(SO4)3, which melt incongruently, and MSc(SO4)2, which on heating decompose in the solid state.  相似文献   

7.
陈梓云  彭梦侠 《无机化学学报》2007,23(12):2091-2096
相同的水热反应条件下4-氨基-二(2-吡啶基)-1,2,4-三氮唑(abpt)、KSCN与钴盐(CoCl2·6H2O)反应合成了2种新的钴配合物:零维的单核配合物[CoSCN(abpt)] ()和二维的无机层状配合物K2[Co3(OH)2(SO4)3(H2O)2] (),并通过元素分析和红外光谱对其进行了表征。配合物的晶体属于单斜晶系,P21/c空间群。配合物晶体属于正交晶系,Cmc21空间群。在配合物中,abpt和SCN-配体都参与配位与Co(Ⅱ)离子形成了2个不同的单核单元,这些单核单元又通过S原子和N原子之间的氢键作用连成了三维超分子结构;在配合物中,abpt配体没有参与配位,而SCN-配体则被氧化成了SO42-离子并与Co(Ⅱ)离子配位形成了二维配位层状结构,相邻层之间进一步通过氢键作用形成了沿c轴方向有孔道的三维超分子网络,这些孔道里面填充着反离子K+。  相似文献   

8.
The synthesis of the title compounds by a variety of routes is described. These routes involve the oxidation of antimony(III)fluoride by bis(fluorosulfuryl)peroxide and the use of non-statistical ligand redistribution reactions. Complex formation with ClO2SO3F leads to ClO2[SbFn(SO3F)6-n], with n=3 or 4. Polarized Raman data and low temperature infrared data are reported. All antimony(V)fluoride-fluorosulfates are found to have fluorosulfate bridges with SbF3(SO3F)2 and SbF4(SO3F) being polymers. Ionic formulations for the ClO+2 complexes are again based on vibrational spectra.  相似文献   

9.
Fe2(SO4)3/γ-Al2O3固体超强酸的Mössbauer谱研究   总被引:1,自引:0,他引:1  
采用浸渍法制备了一系列Fe2(SO4)3/ γ-Al2O3型固体超强酸样品,用Moessbauer谱和XRD研究了不同温度处理对样品中铁组分的存在状态及稳定性的影响。结果表明,随Fe2(SO4)3含量的变化,铁组分可以在γ-Al2O3表面以单层分散和无定形形式存在;当温度≥600℃时,无定形状态的Fe2(SO4)3又生成晶态的Fe2(SO4)3,而形成的晶态Fe2(SO4)3即使在700℃时也不分解。  相似文献   

10.
PbMn(SO4)2 has been synthesized in an evacuated quartz tube. The nuclear and magnetic crystal structures have been determined using powder X-ray and neutron diffraction. This material crystallizes in the enantiomorphic space group pair P41212(92) and P43212(96), forming a double-helical arrangement of Pb2+ and Mn2+ cations. The Mn2+O6 octahedra are distorted. Each 3d5 Mn2+ has four nearest-neighbors and four next-nearest-neighbors adopting a frustrating arrangement. The compound orders antiferromagnetically at 5.5 K. Field dependent specific heat and magnetization measurements show that TN is suppressed to 3.3 K when μ0H=9 T.  相似文献   

11.
[Fe(CO)2 {P(OR)3}2 (SO2)] complexes (R = aryl) exist in solution as equilibrium mixtures of two isomers; both have been shown by X-ray diffraction studies (where R = Ph or o-MeC6H4) to have planar coordination about SO2 and trigonal bipyramidal coordination about Fe, but in one isomer (R = Ph) the equatorial plane is occupied by SO2 and two CO ligands whilst in the other one (R = o-MeC6H4) it is occupied by the SO2 and two P ligands.  相似文献   

12.
HC(SO2F)3 has been prepared and characterized. It turned out to be a strong acid, comparable to mineral acids. In aqueous solution the salts of the type Cs+C(SO2F)3? are formed. The anion, as found by crystal structure analysis contains planar CS3 configuration.Quite in contrast to these findings HC(OSO2F)3 is not even soluble in water.Derivatives of HC(SO2F)3 have been prepared so far CH3C(SO2F)3 FC(SO2F)3 ClC(SO2F)3 BrC(SO2F)3 JC(SO2F)3The heavier halogen derivatives ( Cl, Br, J ) are oxidizing agents (‘positive halogen’).A mixture of cis- and trans- (HO)2TeF4 is obtained if HOTeF5 and Te(OH)6 are melted together. The mixture of the isomeres have been transfered into the corresponding silylesters cis- and trans- (R3SiO)2TeF4, which could be separated by fractional crystallisation and distillation.Without conformational change the pure silylesters have been reacted back to pure cis- (HO)2TeF4 and trans- (HO)2TeF4 by means of anhydrous HF. Both cis- and trans (HO)2TeF4 have been reacted with ClF to give cis- and trans- (ClO)2TeF4, yellow liquids. The latter react with elemental bromine to the rather unstable cis- and trans- (BrO)TeF4, red liquids.Starting with cis-(HO)2TeF4 and XeF2 a polimer Xenon compound of the formula
All materials have been characterized by melting point and vapour pressure, 19 F - nmv spectroscopy, vibrational spectroscopy, and elemental analysis.  相似文献   

13.
The iridium(I) complex [Ir(CO2Me)(CO)2(PPh3)2] undergoes a transesterification reaction with the alcohols CH2C(R)CH2OH (R = H, Me), MeCCCH2CH2OH, and HOCH2CH2OH to afford the complexes
[Ir(CO2CH2CH2CMe)(CO)2(PPh3)2] and [Ir(CO2CH2CH2OH)(CO)2(PPh3)2], respectively. In contrast the acetylenic alcohol HCCCH2CH2OH gives [Ir(CCCH2CH2OH)(CO)PPh3)2]. Some reactions of the new complexes are described.  相似文献   

14.
The first indium sulfate coordination complex, (2,2′-bipy)[In2(OH)2(H2O)](SO4)2 (2,2′-bipy=2,2′-bipyridyl) was hydrothermally synthesized and characterized by single-crystal X-ray diffraction (XRD), the powder XRD, elemental analysis, inductively coupled plasma (ICP) analysis, thermogravimetric analysis (TGA), IR spectroscopy and fluorescent spectroscopy. It is noteworthy that this compound exhibits a novel two-dimensional layer structure, which is built up from two distinct motifs, a butlerite-type chain and a single 4-ring (S4R) unit. The adjacent layers are stably packed together and extended into three-dimensional supramolecular arrays via π-π stacking interactions of the 2,2′-bipy ligands. Additionally, this compound shows strong fluorescent property at room temperature, which may be assigned to ligand-centered π*-π transitions.  相似文献   

15.
Powder specimens of the layered triangular-lattice antiferromagnets RbFe(MoO4)2 and CsFe(SO4)2 were prepared and neutron powder diffraction experiments were carried out in order to determine the magnetic structure. The magnetic structure of both compounds is the so-called 120° structure in the triangular plane and is incommensurate between the planes. The ordered moments are confined in the basal ab-plane. It is also found that RbFe(MoO4)2 exhibits structural phase transition at around 190 K from to .  相似文献   

16.
The title compound was synthesized by reaction of Cu(ClO4)2, picolinic acid and carbamide in C2H5OH/CH3CN solution, and characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=14.0481(8), b=9.0130(5), c=18.626(1)?, V=2358.3(2)?3Z=4, Dx=1.771g·cm-3, μ=1.235mm-1 and F(000)=1276. The final R factor is 0.0440 for 1434 observed reflections. The X-ray analysis revealed that the copper(Ⅱ) atom is coordinated by two picolinic ligands in the equatorial plane, while the two oxygen atoms of perchlorate occupy the axial positions of octahedron with lengthened Cu-O distances, resulting in a 4+2 elongated octahedral environment. In the compound, there also exist two protonated carbamide cations for charge balance. CCDC: 195354.  相似文献   

17.
Diazoaminobenzene (DAAB) formed slowly when aniline was reacted with Zn(py)2(ONO)2 in dichloroethane at 60°. The rate of reaction was followed by measuring the DAAB concentration spectrophotometrically at 353 nm. Complex concentrations ranged from 5 to 30 mM, while those of aniline were from 100 to 900 mM. The kinetic data were explained by a mechanism involving a pre-equilibrium, wherein aniline displaced a nitrite ion from the zinc complex. This was followed by a slow reaction of the free nitrite ion with the solvent, forming a highly reactive nitrosating species.  相似文献   

18.
The solubility diagram of the system NaAl(SO4)2–CsAl(SO4)2–H2O was investigated at 25°C. This is a system in which -and -alums participate. The fields of cristallization are outlined. There is one wide field of cesium aluminium alum and one, very narrow, of sodium aluminium alum. The eutonic point of the system lies at the composition of the liquid phase corresponding to 27.90 wt.% NaAl(SO4)2 and 0.008 wt.% CsAl(SO4)2. It was found that mixed crystals are not formed in the system. The solid phases were investigated by X-ray diffraction andDTA.  相似文献   

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