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1.
1,4-Diazabicyclo [2,2,2]octane N,N′-dioxide di(perchlorate), C6H14N2O22 +·2ClO4−, was synthesized and separated as colorless block crystals. Differential scanning calorimetry detected that this compound underwent a reversible phase transition at ca. 216 K with a hysteresis of 5.5 K width, which was also confirmed by dielectric measurements. Single crystal X-ray diffraction data suggested that there was a transition from a room temperature phase with the space group of P21/c (a = 6.815(7) Å, b = 12.644(13) Å, c = 8.676(9) Å, β = 101.466(15)°, V = 732.7(13) Å3, Z = 4) to a low temperature one with a space group of P21 (a = 9.892(8) Å, b = 12.559(10) Å, c = 17.401(13) Å, β = 92.065(8)°, V = 2160(3) Å3, Z = 2). Crystallographic analysis showed that it belonged to chiral space group P21 with ferroelectric behaviors, and a typical ferroelectric feature of electric hysteresis loop was obtained in the low temperature phase. The disorder-order transformation of H2-Dabcodo2 + cation and ClO4− anion as well as the change of hydrogen bonds may drive the phase transition. 相似文献
2.
《Catalysis communications》2003,4(10):537-542
The crystal structures and chemical compositions of the M1 and M2 phases proposed as active and selective in propane oxidation to acrylic acid over the bulk mixed Mo–V–Te–O catalysts were investigated by the transmission electron microscopy, coupled with energy dispersive analysis of X-rays. The results revealed that the crystal structure of the M1 phase is orthorhombic with space group Pbca, lattice parameters a=21.25 Å, b=27.14 Å, c=4.03 Å and composition Mo0.64V0.32Te0.1O3.05 (Mo/V ∼2), whereas M2 is hexagonal with space group P6mm, lattice parameters a=7.10 Å, c=4.05 Å and composition Mo1.79V1.85Te0.1O11.36 (Mo/V ∼1). The M1 phase was dominant in the Mo–V–Te–O catalyst. The results obtained indicated that the bulk Mo–V–Te oxides represent a well-defined model catalytic system for the studies of the surface molecular structure-activity/selectivity relationships in propane oxidation to acrylic acid. 相似文献
3.
《Journal of the European Ceramic Society》2007,27(4):2045-2052
Highly stoichiometric and phase pure barium hexaferrite has been synthesized by co-precipitation as well as a solid-state preparative method using high purity nitrates, oxides and carbonates of iron(III), barium(II) and ammonium hydroxide. The isochronal and isothermally measured complex permittivity and dielectric loss tangents over 1 MHz–1 GHz in frequency remained relatively stable until a sintering temperature between 1100 and 1300 °C. A high value of relative permittivity of 32 and low loss tangent of 0.0329 indicate suitable high frequency characteristics for barium hexaferrite. The measured apparent densities before and after each firing cycle showed a monotonic increase. The crystal structure determined from X-ray diffraction studies confirmed the presence of single phase belonging to the theoretical space group P63/mmc with calculated cell parameters of a = b = 5.895 Å and c = 23.199 Å. In addition the DTA hexaferrite formation temperature was found to be 1050 °C. 相似文献
4.
《Journal of the European Ceramic Society》2006,26(6):875-882
Solid solutions of (x)Re(Co1/2Ti1/2)O3–(1 − x)CaTiO3 (Re = La and Nd, abbreviated to xLCT and xNCT, respectively) where x = 0, 0.25, 0.5, 0.75 and 1 have been fabricated using solid state synthesis. Samples have been examined using X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy (TEM) and their dielectric properties measured at microwave (MW) frequencies. Formation of single phase solid solutions were confirmed by XRD and the measured lattice parameters varied linearly from LCT (a = 5.66 Å, b = 7.867 Å and c = 5.494 Å) and NCT (a = 5.636 Å, b = 7.914 Å and c = 5.461 Å) to CT (a = 5.596 Å, b = 7.731 Å and c = 5.424 Å). XRD and TEM confirmed both in-phase and antiphase rotations of O-octahedra consistent with an a−a−c+ tilt system across the entire solid solution series. Electron diffraction revealed that LCT and NCT have reflections associated with B-site cation ordering which is absent for x ≤ 0.75. MW dielectric measurements showed that LCT and NCT were highly insulating with microwave quality factor (Qf0) values of 39,000 and 34,000, respectively. Compositions anticipated to have a zero temperature coefficient of resonant frequency (τf) are 0.48LCT-CT and 0.52NCT-CT with ɛr = 45 and Qf0 ∼ 5000 and ɛr = 43 and Qf0 ∼ 4000, respectively. 相似文献
5.
Paula M. Cantos Mark Frisch Christopher L. Cahill 《Inorganic chemistry communications》2010,13(9):1036-1039
A 3D uranium-pyridinedicarboxylate, compound (1) [UO2(C7H3NO4)], represents the final member of a series of materials incorporating a series of 2,n-pyridinedicarboxylic (pydc) acids (n = 3,4,5,6). The resulting crystal structure [FW = 419.13, monoclinic, P21/n, a = 9.0096(3) Å, b = 8.1371(2) Å, c = 11.6954(4) Å, V = 852.45 Å3, Z = 4] was determined by single crystal X-ray diffraction and fluorescent properties were investigated. Additionally, the complete series of uranium-2,n-pydc materials was examined on a basis of fluorescent behaviors and architectural similarities. 相似文献
6.
To determine the tautomeric form of the hetarylazo indole dye 3-(5-methylthiazol-2-yldiazenyl)-2-phenyl-1H-indole (1), 1-methyl-3-(thiazol-2-yldiazenyl)-2-phenyl-1H-indole (2) was synthesized as a model compound and both molecules were characterized by single crystal X-ray diffraction. (1) crystallized in the monoclinic system, space group C2/c, a = 31.064(2), b = 7.4051(5), c = 27.7138(18) Å, β = 97.617(1)°, V = 6318.9(7) Å3, Z = 8, while dye 2 crystallized in the monoclinic system, space group P21/n, a = 11.4660(11), b = 9.8223(9), c = 14.2049(14) Å, β = 97.418(2)°, V = 1586.4(3) Å3, Z = 4. The asymmetric unit of 1 contains two crystallographically independent molecules, in which geometries and conformations differ slightly, while there is only one molecule in the asymmetric unit for 2. The intermolecular N–H?N hydrogen bonds in (1) link the molecules, via parallel, infinite sheets, along the a axis and stabilize the crystal structure; in 2, there is no classical intermolecular hydrogen bond. 相似文献
7.
Richard S. Herrick Brenton R. Franklin Christopher J. Ziegler Anıl Çetin 《Inorganic chemistry communications》2009,12(12):1209-1211
The reaction of 1,1′-ferrocenedicarbonyl chloride with pyrazole or 3,5-dimethyl pyrazole generates novel 1,1′-ferrocene bis(amide) compounds 1 and 2, respectively. The crystal structure of 1 shows that the pyrazole rings are essentially co-planar with each other and with the cyclopentadienyl rings. Attempts to use the complexes as a chelating ligand were unsuccessful. Instead, treatment of 1 or 2 with Mo(CO)4(pip)2, pip = piperidine, led to displacement of the pyrazole ligands and formation of the known amide compound, 1,1′-ferrocene bis carbonyl piperidine. Replacement of the pyrazole is ascribed to the weakness of the amide bond caused by the aromaticity of the pyrazole ring. Crystal data for C18H14FeN4O2 (1): monoclinic P2(1)/c, a = 13.3907(18) Å, b = 10.2112(14) Å, c = 11.3082(16) Å, β = 105.209(2)°, V = 1492.1(4) Å3, Z = 4. 相似文献
8.
Ba(dl-C4H4O5) — An alkaline earth metal-dicarboxylate hybrid crystal with the synergy of multi-bonds
The organic–inorganic hybrid crystal, Ba(dl-C4H4O5), has been firstly prepared by hydrothermal method. It crystallizes in monoclinic crystal system with a centrosymmetric space group of P21/c with a = 8.150(2) Å, b = 10.447(3) Å, c = 6.938(2) Å, β = 95.599(3)° and Z = 4. In this compound, the coexistence of organic ligand and the alkaline earth metal cation leads to the diversity of chemical bonds. The synergy of Ba–O ionic bonds and hydrogen bonds strengthens the crystal structure. Characterization of this earth metal-dicarboxylate hybrid crystal is described by using powder X-ray diffraction, infrared spectroscopy, UV–vis–NIR diffuse reflectance spectrum and the TG curve. In addition, Ba(dl-C4H4O5) possesses a short ultraviolet cutoff wavelength lower than 230 nm determined by the electronic transition of C–O group, which signifies the potential use in UV region applications. And the electronic structure and optical properties are studied by first principle calculation method, which obtains a birefringence value of 0.04. 相似文献
9.
Tolulope O. Salami Stephanie N. Patterson Victoria D. Jones Antonio Masello Khalil A. Abboud 《Inorganic chemistry communications》2009,12(11):1150-1153
A rare two-dimensional layered inorganic–organic hybrid material, strontium sulfonate Sr[C2H4(SO3)2] was synthesized by hydrothermal reaction of strontium chloride hexahydrate and ethane disulfonic acid at 160 °C. Single-crystal X-ray diffraction was utilized for structural determination. Data showed that the compound, crystallized in the monoclinic system and space group of C2/c. With cell parameters a = 8.3183(7) Å, b = 5.4416(5) Å and c = 14.9784(13) Å. The new material was extensively studied by DRIFT-infrared spectroscopy, thermogravimetric analysis, SEM and powder X-ray diffraction. Results show that the compound is thermally stable. 相似文献
10.
Guo-Wu Wang Cheng-Ling Pan Ke-Chang Li Xiao-Bing Cui Hai-Tao Wang Yan Wang Shu-Yun Shi Ji-Qing Xu 《Inorganic chemistry communications》2010,13(1):116-118
A novel compound [P2W18M3O68][Cu(en)2]4·7H2O·2OH? (M = 0.5W + 0.5Cu) 1 which contains the first example of extended structure constructed from Knoth-type sandwich polyoxoanions and transition metal coordination complexes has been hydrothermally synthesized and characterized by elemental analysis, IR spectrum, UV–Vis spectrum and single-crystal X-ray diffraction analysis. Crystal data for 1: triclinic, space group, P-1, a = 13.2718(7) Å, b = 13.6432(8) Å, c = 25.7307(15) Å, α = 104.7340(10)°, β = 96.7630(10)°, γ = 90.0330(10)°, V = 4472.2(4) Å3, Z = 2. Structure solution and refinement based on 1090 parameters gave R1 (wR2) = 0.0409 (0.0993). 相似文献
11.
A new mixed metal borate LiBa1.5[B5O8(OH)3] (1) has been hydrothermally synthesized and structurally characterized by FT-IR spectroscopy, powder X-ray diffraction, single crystal X-ray diffraction, and thermogravimetric analysis, respectively. 1 crystallizes in the monoclinic system, space group C2/c, a = 11.2839(7) Å, b = 7.3974(4) Å, c = 20.7151(13) Å, β = 103.392(6)°, V = 1682.10(17) Å3 and Z = 8. The structure consists of infinite one-dimensional (1-D) borate chains constructed from B5O9(OH)36 − cluster units. These BO chains are further linked by the Ba2 + and Li+ cations to form a 3-D framework. 相似文献
12.
《Ceramics International》2016,42(13):14999-15004
Unfilled tungsten bronze ceramics with a composition of Ba4SmFe0.5Nb9.5O30 were prepared by the conventional solid-state sintering method. The phase, microstructure, dielectric and ferroelectric properties were studied. Room temperature XRD results indicated that the ceramic occurs in the tetragonal space group P4bm phase with cell parameters of a=b=12.4712(2) Å and c=3.9430(2) Å. The temperature-dependent dielectric properties, XRD data and Raman spectra data indicated that BSFN ceramics exhibit no phase changes from 35 °C to 450 °C. Fitting of a Vogel-Fulcher relationship with an activated energy Ea of 0.11 eV indicates an unambiguous dielectric relaxor state near room temperature. Furthermore, the BSFN ceramics exhibited residual polarization and coercive field of 3.45 µC/cm2 and 24.65 kV/cm, respectively. 相似文献
13.
A novel 1-dimensional U(VI) phosphonoacetate, UO2(O3PCH2CO2H)(H2O)·2H2O (1), has been synthesized from the room temperature reaction of uranium nitrate and phosphonoacetic acid (H3PPA) in water. The compound crystallizes in a monoclinic space group (P21, a = 8.3517(5) Å, b = 7.0013(4) Å, c = 8.3728(5) Å, β = 107.310(1)°, Z = 2) and exhibits bonding to the UO22+ through both phosphonate and carboxylate oxygen atoms of the acid unit. The crystal structure, thermal and fluorescent behaviors, and role of UO22+ hydrolysis in the context of ambient versus hydrothermal syntheses are discussed. 相似文献
14.
Ying Wei Hermann Gies Zhijian Tian Bernd Marler Yunpeng Xu Lei Wang Huaijun Ma Renyan Pei Keda Li Bingchun Wang 《Inorganic chemistry communications》2010,13(11):1357-1360
A new layered ammonium nickel(II) diphosphate, (NH4)2[Ni3(P2O7)2(H2O)2], has been synthesized ionothermally in the ionic liquid 1-butyl-3-methyl imidazolium bromide and characterized by powder X-ray diffraction, elemental analysis, scaning electron microscopy, thermogravimetry etc. The results of the characterization show that the crystal adopts the monoclinic space group P21/a with the lattice constants a = 9.23529(2) Å, b = 7.98489(2) Å, c = 9.40772(2) Å, β = 100.2608(2)° and Z = 2. Its structure consists of chains of cis- and trans-edge-sharing [NiO6]-octahedra linked via [P2O7] units to form layers of [Ni3(P2O7)2(H2O)2]2? in the ab plane. Adjacent layers are separated in the c-direction by ammonium ions. 相似文献
15.
Xiao-Rui Lv Fu-Kai Zhao Xiao-Ling Guo Yun-Yin Niu Na Xu Hong-Wei Hou Yao-Ting Fan Dong Sun Yu Zhu 《Inorganic chemistry communications》2009,12(7):653-656
A novel cation-templated 3D cuprous thiocyanate polymer, {(bppt)[Cu2(NCS)4]}n, bppt = 1,5-bis (pyridinium) pentane, was hydrothermally synthesized and structurally characterized. The compound crystallizes in monoclinic system, space group P2(1)/c with cell parameters of a = 10.1571(8) Å, b = 15.9785(13) Å, c = 15.3983(12) Å, V = 2407.4(3) Å3, Z = 4, Dc = 1.622 g cm?3, F(0 0 0) = 1192, μ = 2.133 mm?1, R1 = 0.0551, wR2 = 0.1246. In the polymeric architecture, Cu2(NCS)4 dimer is connected by NCS? bridging ligand to constitute a infinite 3D framework with the organic cation bppt trapped in it. Photoluminescence investigation reveals that a slightly red shift of 27 nm for the complex takes place comparing with the organic cation. 相似文献
16.
Jia-Min Li Jin-Zhou Li Heng-Qiang Zhang Li-Ying Xu 《Inorganic chemistry communications》2010,13(5):573-576
A new cobalt complex, [Co(L)2·(H2O)2](HL = 4-hexanoyl-3-methyl-1-phenyl-1H -pyrazol-5(4H)-one), was synthesized by us. The complex was characterized by single crystal X-ray diffraction, IR, UV, fluorescence spectra and thermogravimetric analysis. The results of characterization showed that the crystal is monoclinic system with crystal parameters: a = 15.2439(12) Å, b = 7.4101(6) Å, c = 15.7381(18) Å, and Z = 2, S = 1.074. It was found that the Co2+ is located in the inversion center of the complex. The Co(II) had an ideal octahedral coordination environment with four oxygen atoms of HL ligands in the equatorial plane and two water molecules in axial positions. The complex exhibits yellow emission as the result of the fluorescence from the intraligand emission excited state. 相似文献
17.
Mariola Puszyńska-Tuszkanow Marek Daszkiewicz Gabriela Maciejewska Maria Cieslak-Golonka 《Inorganic chemistry communications》2009,12(6):484-486
A novel Cu(II) coordination polymer, [Cu(ox)(DMSO)2]n (1) (ox-oxalate dianion, DMSO-dimethyl sulphoxide) has been prepared in the reaction of copper nitrate dihydrate and allantoin (5-ureidohydantoin) in DMSO/water solution. Compound (1) crystallizes in the monoclinic, space group P121/c1 with a = 5.1785(7), b = 13.6311(18), c = 8.5386(12) Å, β = 107.524(12)°, V = 574,76(14) Å3, Z = 4, Dcal = 1779 mg/m3, R1 = 0.0449. The metal ion coordinates through four oxygen atoms belonging to two bidentate bridging oxalate ligands, and two oxygen atoms from two DMSO ligands forming an elongated octahedron. The crystal structure was confirmed by FT-IR and Uv–vis spectroscopic data. 相似文献
18.
Gao-Juan Cao Wei-Hui Fang Shou-Tian Zheng Guo-Yu Yang 《Inorganic chemistry communications》2010,13(9):1047-1049
An organically-templated chiral borogermanate (CH3NH3)2[Ge(B4O9)] (1), has been solvothermally synthesized and characterized by elemental analysis, IR, PXRD, TGA, single-crystal X-ray diffraction and UV–vis spectrum. It crystallized in the monoclinic space group C2 (No. 5) with a = 10.249(1) Å, b = 9.449(1) Å, c = 6.956(2) Å, β = 131.76(2)°, V = 502.43(19) Å3, Z = 2. The structure is constructed by alternate linkage of GeO4 tetrahedra and B4O9 clusters to form a zeotype framework with diamond topology. Four intersecting channels with different sizes are observed. Large circular 10-ring channels are clearly extended along the [001] direction, 9-ring channels are running along the [101], [110], and [112] directions, respectively. Additionally, two pairs of the right- and left-handed channels couple together along the [100] and [010] directions, respectively. The preliminary investigations show that compound 1 exhibits second-harmonic generation (SHG) response and ferroelectric properties. 相似文献
19.
A novel transition-metal (TM) complex based on Lindqvist polyoxoniobate K10[(Nb6O19)CrIII(H2O)2]2·28H2O (1) has been synthesized by a new two-pot synthesis strategy and structurally characterized by single crystal X-ray diffraction analysis, IR spectrum, UV–vis spectroscopy, XRPD and TG analysis. Compound 1 crystallizes in the C2/m space group with a = 32.143(19) Å, b = 10.030(6) Å, c = 12.878(8) Å, β = 110.611(9)°, and V = 3886(4) Å3. X-ray structure analysis reveals that polyanion [(Nb6O19)CrIII(H2O)2]210 − (1a) represents the first example of two nuclear dimeric polyoxoniobate, in which two Lindqvist anions [Nb6O19]8 are sandwiched by two {CrIII(H2O)2} groups. Further, 1 exhibits photocatalytic H2 evolution activity. 相似文献
20.
Two new organic-inorganic hybrid materials, 1-(2-fluorophenyl)piperazine-1,4-diium tetrachlorocuprate, (C10H15FN2)[CuCl4] (I) and 1-(2-fluorophenyl)piperazin-4-ium nitrate, (C10H14FN2)[NO3] (II), have been synthesized by an acid/base reaction at room temperature in the presence of 1-(2-fluorophenyl)piperazine as an organic-structure directing agent and their structures were determined by single crystal X-ray diffraction. Compound (I), (C10H15FN2)[CuCl4], crystallizes in the monoclinic system and P21/c space group with a = 7.5253 (2), b = 20.6070 (7), c = 9.7281 (3) Å, β = 103.6730 (17)°, V = 1465.82 (8) Å3 with Z = 4. Full-matrix least-squares refinement converged at R = 0.037 and wR(F2) = 0.088. Compound (II), (C10H14FN2)[NO3], belongs to the monoclinic system, space group P21/c with the following parameters: a = 10.8034 (2), b = 7.5775 (1), c = 14.4670 (3) Å, β = 111.761 (2)°, V = 1099.91 (4) Å3 and Z = 4. The structure was refined to R = 0.044, wR(F2) = 0.136.In the structures of (I) and (II), the anionic and cationic entities are interconnected by means of set of hydrogen bonding contacts forming three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces and the contacts of the four different chloride atoms were notably compared. The results of the optimized molecular structure are presented and compared with the experimental one. The Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gap of both compounds were computed. The vibrational absorption bands were identified by infrared spectroscopy. Theory (DFT) calculations of normal mode frequencies are compared with experimental ones. 相似文献