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1.
本文报导了硫氰酸铀铣(18-冠-6)铵和硫氰酸铀酰(18-冠-6)钾两种固体配合物的合成。由测定其物理常数及谱学数据, 确定了配合物的组成为[(C12H24O6)M]2UO2(NCS)4H2O(M=NH4, K)。X射线结构分析确定了二种单晶的结构。铵配合物属正交晶素, 空间群为Fdd2, 钾配合物属单斜晶系, 空间群为C2/c。  相似文献   

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Conclusions The authors have synthesized anilinium chloranilate (NH3C6H5)2(C6O4Cl2) (I) and acid ammonium chloranilate dihydrate NH4H5O2(C6O4C12) (II). By x-ray structural analysis they have established their crystal structures. In crystals of NH4H5O2(C6O4Cl2) they find the ion H5O 2 + with the unusual O-H-O bond length of 2.81 A. The anions of chloranilic acid in crystals (I) and (II) have equal charges but different structures.Translated from IzvestiyaAkademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 487–489, March, 1981.  相似文献   

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FT IR and FT Raman spectra of Ag3(PO2NH), (Compound 1), Na3(PO2NH)3 x H2O (Compound II), Na3(PO2NH)3 x 4H2O (Compound III), [C(NH2)3]3(PO2NH)3 x H2O (Compound IV) and (NH4)4(PO2NH)4 x 4H2O (Compound V) are recorded and analyzed on the basis of the anions, cations and water molecules present in each of them. The PO2NH- anion ring in compound I is distorted due to the influence of Ag+ cation. Wide variation in the hydrogen bond lengths in compound III is indicated by the splitting of the v2 and v3 modes of vibration of water molecules. The NH4 ion in compound V occupies lower site symmetry and exhibits hindered rotation in the lattice. The correlations between the symmetric and asymmetric stretching vibrations of P-N-P bridge and the P-N-P bond angle have also been discussed.  相似文献   

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FTIR and single crystal Raman spectra of (CH3)2NH2Al(SO4)2 x 6H2O have been recorded at 300 and 90 K and analysed. The shifting of nu1 mode to higher wavenumber and its appearance in Bg species contributing to the alpha(xz) and alpha(yz) polarizability tensor components indicate the distortion of SO4 tetrahedra. The presence of nu1 and nu2 modes in the IR spectrum and the lifting of degeneracies of nu2, nu3, and nu4 modes are attributed to the lowering of the symmetry of the SO4(2-) ion. Coincidence of the IR and Raman bands for different modes suggest that DMA+ ion is orientationally disordered. One of the H atoms of the NH2 group of the DMA+ ion forms moderate hydrogen bonds with the SO4(2-) anion. Al(H2O)6(3+) ion is also distorted in the crystal. The shifting of the stretching modes to lower wavenumbers and the bending mode to higher wavenumber suggest that H2O molecules form strong hydrogen bonds with SO4(2-) anion. The intensity enhancement and the narrowing of nu1SO4, deltaC2N and Al(H2O)6(3+) modes at 90 K confirm the settling down of the protons in the hydrogen bonds formed with H2O molecules and NH2 groups. This may be one of the reasons for the phase transition observed in the crystal.  相似文献   

6.
The 1/2V2O5-H2C2O4/H3PO4/NH4OH system was investigated using hydrothermal techniques. Four new phases, (NH4)VOPO(4).1.5H2O (1), (NH4)0.5VOPO(4).1.5H2O (2), (NH4)2[VO(H2O)3]2[VO(H2O)][VO(PO4)2]2.3H2O (3), and (NH4)2[VO(HPO4)]2(C2O4).H2O (4), have been prepared and structurally characterized. Compounds 1 and 2 have layered structures closely related to VOPO(4).2H2O and A0.5VOPO4.yH2O (A = mono- or divalent metals), whereas 3 has a 3D open-framework structure. Compound 4 has a layered structure and contains both oxalate and phosphate anions coordinated to vanadium cations. Crystal data: (NH4)VOPO(4).1.5H2O, tetragonal (I), space group I4/mmm (No. 139), a = 6.3160(5) A, c = 13.540(2) A, Z = 4; (NH4)0.5VOPO(4).1.5H2O, monoclinic, space group P2(1)/m (No. 11), a = 6.9669(6) A, b = 17.663(2) A, c = 8.9304(8) A, beta = 105.347(1) degrees, Z = 8; (NH4)2[VO(H2O)3]2[VO(H2O)][VO(PO4)2]2.3H2O, triclinic, space group P1 (No. 2), a = 10.2523(9) A, b = 12.263(1) A, c = 12.362(1) A, alpha = 69.041(2) degrees, beta = 65.653(2) degrees, gamma = 87.789(2) degrees, Z = 2; (NH4)2[VO(HPO4)]2(C2O4).5H2O, monoclinic (C), space group C2/m (No. 12), a = 17.735(2) A, b = 6.4180(6) A, c = 22.839(2) A, beta = 102.017(2) degrees, Z = 6.  相似文献   

7.
The IR and Raman spectra and the thermal behaviour of the isomorphous compounds (NH4)3Ga(C2O4)3·3H2O and (NH4)3Al(C2O4)3·3H2O were investigated. Detailed stoichiometries, sustained by TG, DTA and IR spectroscopic analyses, were found in both cases. Different results, associated with the different polarizing powers of the metal cations, were obtained. The first evidence was found of the formation of basic gallium carbonates.  相似文献   

8.
以一定比例正辛酸和月桂酸为第一配体,通过皂化法合成了脂肪酸铕配合物,并溶于甲基丙烯酸甲酯(MMA)单体通过本体聚合得到了含脂肪酸铕的PMMA光致发光聚合物材料AxByEu/PMMA(A为正辛酸根,B为月桂酸根,x、y分别表示正辛酸和月桂酸的摩尔比). 考察了不同的第二配体(咔唑、二甲基-联吡啶、邻菲罗啉、噻吩甲酰三氟丙酮HTTA)对脂肪酸铕聚合物发光性能的影响,选择出合适的第二配体HTTA,合成了A3Eu/HTTA/PMMA聚合物. 通过红外光谱、紫外光谱及荧光光谱测试技术对配合物及聚合物的结构和荧光性能进行表征. 结果表明,合成的含脂肪酸铕配合物及其聚合物均具有很好的光致发光性能,紫外激发能发射Eu3+离子的特征红光. 当HTTA的质量分数减小至MMA的0.02%时,仍能很好地促进体系的发光,且不影响聚合物本身的透明性.  相似文献   

9.
Three new strontium vanadium borophosphate compounds, (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O (Sr-VBPO1) (1), (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O (Sr-VBPO2) (2), and (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4][V2P2BO12]6 10H2O (Sr-VBPO3) (3) have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine, 1,3-diaminopropane, and 1,4-diaminobutane. Compound 1 has a chain structure, whereas 2 and 3 have layered structures with different arrangements of [(NH4) [symbol: see text] [V2P2BO12]6] cluster anions within the layers. Crystal data: (NH4)2(C2H10N2)6[Sr(H2O)5]2[V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 21.552(1) A, b = 27.694(2) A, c = 20.552(1) A, beta = 113.650(1) degrees, Z = 4; (NH4)2(C3H12N2)6[Sr(H2O)4]2[V2P2BO12]6 17H2O, monoclinic, space group I2/m (no. 12), a = 15.7618(9) A, b = 16.4821(9) A, c = 21.112(1) A, beta = 107.473(1) degrees, Z = 2; (NH4)3(C4H14N2)4.5[Sr(H2O)5]2[Sr(H2O)4] [V2P2BO12]6 10H2O, monoclinic, space group C2/c (no. 15), a = 39.364(2) A, b = 14.0924(7) A, c = 25.342(1) A, beta = 121.259(1) degrees, Z = 4. The differences in the three structures arise from the different steric requirements of the amines that lead to different amine-cluster hydrogen bonds.  相似文献   

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The polyoxometalate (NH(4))(6)H(2)(CeMo(12)O(42)).9H(2)O (abbreviated as Ce(IV)Mo(12)) was synthesized, and its Ce(III) form was obtained by exhaustive electrochemical reduction. Both forms are fairly stable in pH 0.0 media. This stability decreases when the pH increases. The Ce(IV) species, in which the central metal is in the f(0) electronic configuration, is found to fluoresce, a feature that is only straightforwardly explained with the Ce(III) state. As the results of a series of experiments converge to confirm the stability of Ce(IV)Mo(12) in the media studied, a suggested rationale is that the emission originates from a higher-energy ligand-to-metal charge transfer and follows a scheme which is ultimately equivalent to the classical metal-centered fluorescence of Ce(III). Detailed studies of the influences of pH and ionic strength were carried out and suggest that protonated and/or ion-paired assemblies are the fluorescent species. A reproducible increase of the fluorescence intensity of Ce(IV)Mo(12) as a function of time was also observed.  相似文献   

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蒋安仁  蒋彤  庞震 《化学学报》1989,47(8):800-803
本文作者曾在用过钨酸分解法制备钨酸的过程中发现, 溶液中W与O2^2^-之比始终为2:1, 这一事实说明溶液中有2:1金属过氧配合物形成, 2:1铂过氧络合物[Mo4O12(O2)2]^4^-文献上已有记载, 但类似的钨配合物尚未见报道。本文制备了这二种配合物, 对比它们的红外和Raman光谱, 并用循环伏安法, 恒电位电解法探讨它们的氧化还原分解体系。  相似文献   

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Vibrational spectra of M4LiH3(XO4)4 family, where M=K, Rb, X=S, Se together with Na5H3(SeO4)4.2H2O and Na2SeO4.H2SeO3.H2O crystals were compared. Similarities and differences are described. The spectroscopic manifestation of the presence of hydrogen bonds is discussed. Position of the bands corresponding to bending type of vibrations (in-plane and out-of plane) of hydrogen bonds is analyzed in the function of temperature. Small dynamic splitting of the bands due to weak interactions between ions is noticed.  相似文献   

18.
The infrared spectra of the oxodiperoxo and triperoxo complexes, (NH4)[VO(O2)2(phen)].2H2O and (NH4)[V(O2)3(phen)].2H2O have been recorded and the observed bands are assigned on the basis of Cs symmetry. Thermogravimetric (TG) and differential thermal analysis (DTA) measurements on these two complexes were also carried out. A detailed mechanism for the mode of thermal decomposition of the two complexes has been given and supported by infrared spectral measurements on the thermal decomposition products. The data obtained agree quite well with the expected structure and indicate that the final thermal decomposition product of these two complexes is V2O5.  相似文献   

19.
High signal-to-noise ratio (S/N) Raman spectra of (NH(4))(2)SO(4) droplets deposited on a quartz substrate were obtained from dilute to supersaturated states upon decreasing the relative humidity (RH). When the molar water-to-solute ratio (WSR) decreases from 16.8 to 3.2, the v(1)-SO(4)(2-) band changes very little, that is, showing a red-shift of only about 1 cm(-1) (from 979.9 to 978.8 cm(-1)) and an increase of its full width at half-maximum (fwhm) from 8.3 to 9.8 cm(-1). Other vibration modes such as v(2)- and v(4)-SO(4)(2-) bands appear almost constantly at 452 and 615 cm(-1). Such kind of a spectroscopic characteristic is different from previous observation on other cations, indicating that the interactions between SO(4)(2-) and NH(4)+ in supersaturated states are similar to those between SO(4)(2-) and H(2)O in dilute states. After fitting the Raman spectra with Gaussian functions in the spectral range of 2400-4000 cm(-1), we successfully extracted six components at positions of 2878.7, 3032.1, 3115.0, 3248.9, 3468.4, and 3628.8 cm(-1), respectively. The first three components are assigned to the second overtone of NH(4)+ umbrella bending, the combination band of NH(4)+ umbrella bending and rocking vibrations, and the NH(4)+ symmetric stretching vibration, while the latter three components are from the strongly, weakly, and slightly hydrogen-bonded components of water molecules, respectively. With a decrease of the RH, the proportion of the strongly hydrogen-bonded components increases, while that of the weakly hydrogen-bonded components decreases in the droplets. The coexistence of strongly, weakly, and slightly hydrogen-bonded water molecules must hint at a similar hydrogen-bonding network of NH(4)+, SO(4)(2-), and H(2)O to that of pure liquid water in supersaturated (NH(4))(2)SO(4) droplets.  相似文献   

20.
Reaction pathways, solvent effects and reaction parameters have been investigated for the water exchange on Keggin-Al13 in the aqueous solution by performing supermolecule density functional theory calculations. The calculated results suggest a dissociative (D) mechanism for water exchange on Keggin-Al13 in the aqueous solution and indicate that both the explicit solvent effect and bulk solvent effect have obvious influence on the energy barriers.  相似文献   

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