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The crystal structure of the new complex vanadium oxide Na6Mg2(VO4)2(V2O7) was solved from X‐ray single‐crystal data. The structure contains VO4 tetrahedra and MgO6 octahedra, linked by corners and forming a complex three‐dimensional framework. A half of the VO4 tetrahedra are connected only to MgO6 octahedra, whereas the others are corner‐sharing, forming V2O7 pyrovanadate groups with statistically random orientations. One unique Mg atom is located at an inversion centre, while the other Mg atom, one unique V atom and five unique O atoms lie on mirror planes.  相似文献   

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Na5[VO4][O] and Na4[VO4][OH] were obtained from reactions of V2O5 with Na2O and additional NaOH in the latter case, respectively, at 600‐700 °C in sealed Ag containers under Ar atmosphere. The crystal structures have been determined from X‐ray single crystal data. The structures contain isolated [VO4]3? complexes and non‐coordinating oxide and hydroxide anions, respectively. Raman and infrared data is compared for both compounds and hydrogen bonding is discussed for Na4[VO4][OH].  相似文献   

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The tribarium dilithium divanadate tetrachloride Ba3Li2V2O7Cl4 is a new vanadate with a channel structure and the first known vanadate containing both Ba and Li atoms. The structure contains four non‐equivalent Ba2+ sites (two with m and two with 2/m site symmetry), two Li+ sites, two nonmagnetic V5+ sites, five O2− sites (three with m site symmetry) and four Cl sites (m site symmetry). One type of Li atom lies in LiO4 tetrahedra (m site symmetry) and shares corners with VO4 tetrahedra to form eight‐tetrahedron Li3V5O24 rings and six‐tetrahedron Li2V4O18 rings; these rings are linked within porous layers parallel to the ab plane and contain Ba2+ and Cl ions. The other Li atoms are located on inversion centres and form isolated chains of face‐sharing LiCl6 octahedra.  相似文献   

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Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 3, pp. 141–145, May–June, 1992.  相似文献   

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鲁晓明  刘顺诚  刘育  卜显和  洪少良 《化学学报》1997,55(10):1009-1018
为研究大环化合物对客体分子的选择性, 合成了通式为[NaL(Et2O)]2Na2Mo8O26的三种新型N-对R苯基氮杂15冠5八钼多酸钠超分子配合物(其中L分别为: N-苯基氮杂15冠5、N-对氯苯基氮杂15冠5和N-对甲苯基氮杂15冠5), 进行了元素分析, 红外光谱与核磁共振等结构参数的表征, 对R基为CH3的标题配合物作了X射线四圆衍射测定, 该晶体属单斜晶系, 空间群为P21/a,a=1.4590(4)nm, b=1.3817(3)nm, c=1.7639(5)nm, β=112.67(2)°, V=3.281(1)nm^3, Mr=2021.3, Dc=2.11g/cm^3,μ=2.37mm^-^1, F(000)=2048, R=0.045和Rw=0.057, 与[Na.(DB18C6)(CH3OH)M6O19和[Na(DB24C8)]2M6O19进行比较,结果表明: 大环化合物不仅对客体金属离子有分子识别性, 而且对与之抗衡的多酸阴离子也具有影响。  相似文献   

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Na5[CuO2](OH)2 has been obtained as orange single crystals from mixtures of NaOH, Na2O and Cu2O in sealed Ag containers. The crystal structure has been refined from X‐ray diffraction data (IPDS data, Pnma, Z = 4, a = 607.4(1) pm, b = 891.2(1) pm, c = 1201.0(2) pm, R1 = 0.03). The characteristic unit is the bent [CuO2]3– complex (∠(O–Cu–O) = 170°). The reactivity of Na5[CuO2](OH)2 has been studied by DSC and in situ X‐ray diffraction techniques. IR spectroscopy has been used for further characterization. The Madelung Part of the Lattice Energy (MAPLE) has been calculated as well.  相似文献   

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在水热条件下合成了一种新型超分子化合物,通过元素分析、红外光谱、热重分析和X射线单晶衍射方法确定了其晶体结构.结构分析表明该晶体属于单斜晶系,C2/m空间群,晶胞参数a = 1.264 3(3) nm, b = 2.106 9(4) nm, c = 1.005 7(2) nm, α = 90°, β = 110.16(3)°, γ = 90°, V = 2.514 9(9) nm3, Z = 2, R1 = 0.061 8, wR2 = 0.179 4.  相似文献   

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以3-叠氮-1,2,4-三唑为配体,PA–(苦味酸根)或HTNR–(2,4,6-三硝基间苯二酚脱去一个羟基的质子后形成的离子)为外阴离子,制备得到了两种新的配合物:[Zn(AZT)4(H2O)2](PA)2∙4H2O和[Zn(AZT)2(H2O)4](HTNR)2∙4H2O。[Zn(AZT)4(H2O)2](PA)2∙ 4H2O的X射线晶体数据表明,中心Zn2+离子与来自4个AZT分子的N原子和2个H2O分子的O原子配位;而对于[Zn(AZT)2(H2O)4](HTNR)2∙4H2O来说,6个配位原子来自2个AZT分子的N原子和4个H2O分子的O原子。在两种配合物中,AZT配体分子的配位点都是三唑环上的4位N原子。H2O分子对于分子间氢键的形成起到了重要的作用,在分子间氢键的作用下形成了配合物的晶体结构。在[Zn(AZT)4(H2O)2](PA)2∙4H2O的晶体结构中,还存在错位面对面π-π堆积作用,它对于晶体结构的形成和稳定性也起到了重要作用。TG-DTG和DSC分析结果显示,[Zn(AZT)2(H2O)4](HTNR)2∙4H2O的热分解过程不如[Zn(AZT)4(H2O)2](PA)2∙4H2O剧烈,原因在于前者分子中含有较多配位水分子和较少AZT配体分子。感度测试结果表明,[Zn(AZT)4(H2O)2](PA)2∙4H2O有一定的火焰感度,而[Zn(AZT)2(H2O)4](HTNR)2∙4H2O却对热不敏感;两种化合物在撞击和摩擦作用下都表现钝感。  相似文献   

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A novel bisperoxovanadium complex, [NH4][VO(O2)2(ima)] (1) (ima = imidazole-4-carboxamide), was synthesized by the reaction of NH4VO3 and ima in the presence of H2O2, and the structure was characterized by single-crystal X-ray technology. The adjacent [NH4][VO(O2)2(ima)] monomers further constructed a 3-D supramolecular framework through intra- and intermolecular hydrogen bonding interactions. The composition of the title complex solution was explored using a combination of multinuclear (1H, 13C and 51V) magnetic resonance, heteronuclear single quantum coherence (HSQC), and variable temperature NMR in a 0.15 mol L?1 NaCl/D2O solution that mimics physiological conditions. According to NMR experimental results, a pair of isomers (Isomers A and B) are observed in aqueous solution, which are attributed to different types of coordination modes between the metal center and the ligands; Isomer B (the main product) has the same coordination structure as the crystal structure of [NH4][VO(O2)2(ima)]. The 51V NMR experiment together with single-crystal X-ray diffraction results indicated that Isomer A is the hexa-coordinated peroxovanadium species while Isomer B is the hepta-coordinated species.  相似文献   

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The structure of Al2Ge2O7 has been determined by using a single crystal. The symmetry is monoclinic (C2c, Z = 4) with unit cell parameters a = 7.132(1) Å, b = 7.741(1) Å, c = 9.702(2) Å, β = 110.62(2)°. The structure is characterized by digermanate groups (Ge2O7) and by AlO5 bipyramids with two common edges forming (AlO3) chains. The relationship with the thortveitite structure is discussed in terms of coordination polyhedra.  相似文献   

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Single crystals of a new silicate carbonate, K2Ca[Si2O5](CO3), have been synthesized in a multi-components hydrothermal solution with a pH value close to neutral and a high concentration of a carbonate mineralizer. The new compound has an axial structure (s.g. P6322) with unit cell parameters a = 5.04789 (15), c = 17.8668 (6) Å. Pseudosymmetry of the structure corresponds to s.g. P63/mmc which is broken only by one oxygen position. The structure consists of two layered fragments: one of the type of the mineral kalsilite (KAlSiO4) and the other of the high-temperature soda-like α-Na2CO3, Ca substituting for Na. The electro-neutral layer K2[Si2O5] (denoted K) as well as the layer Ca(CO3) (denoted S) may separately correspond to individual structures. In K2Ca[Si2O5](CO3) the S-K layers are connected together via Ca-O interactions between Ca atoms from the carbonate layer and apical O atoms from the silicate one, and also via K-O interlayer interactions. A hypothetical acentric structure, sp.gr. P-62c, is predicted on the basis of the order-disorder theory. It presents another symmetrical option for the arrangement of K-layers relative to S-layers. The K,Ca-silicate-carbonate powder produces a moderate SHG signal that is two times larger that of the α-quartz powder standard and close to other silicates with acentric structures and low electronic polarizability.  相似文献   

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Ca2[P4O12] · 4 H2O crystallizes in the monoclinic space group P21/n, a = 7.668, b = 12.895, c = 7.144 Å, β 107.00°, Dx = 2.28 g · cm?3, Z = 2. In the structure there are ringlike anions, which are composed of 4 PO4 tetrahedra connected by oxygen bridges. The Ca2+ are surrounded by 7 oxygen atoms. Each two cation polyhedra are connected by a common edge to pairs which are isolated from one another. The water molecules form hydrogen bridges with one another and with the anion rings.  相似文献   

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