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1.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

2.
The Mx Hy (A O4)z acid salts (M = Cs, Rb, K, Na, Li, NH4; A = S, Se, As, P) exhibit ferroelectric properties. The solid acids have low conductivity values and are of interest with regard to their thermal properties and proton conductivity. The crystal structure of caesium dihydrogen orthophosphate monohydrogen orthophosphate dihydrate, Cs3(H1.5PO4)2·2H2O, has been solved. The compound crystallizes in the space group Pbca and forms a structure with strong hydrogen bonds connecting phosphate tetrahedra that agrees well with the IR spectra. The dehydration of Cs3(H1.5PO4)2·2H2O with the loss of two water molecules occurs at 348–433 K. Anhydrous Cs3(H1.5PO4)2 is stable up to 548 K and is then converted completely into caesium pyrophosphate (Cs4P2O7) and CsPO3. Anhydrous Cs3(H1.5PO4)2 crystallizes in the monoclinic C 2 space group, with the unit‐cell parameters a = 11.1693 (4), b = 6.4682 (2), c = 7.7442 (3) Å and β = 71.822 (2)°. The conductivities of both compounds have been measured. In contrast to crystal hydrate Cs3(H1.5PO4)2·2H2O, the dehydrated form has rather low conductivity values of ∼6 × 10−6–10−8 S cm−1 at 373–493 K, with an activation energy of 0.91 eV.  相似文献   

3.
In poly[[diaquaoxido[μ3‐trioxidoselenato(2−)]vanadium(IV)] hemihydrate], {[VO(SeO3)(H2O)2]·0.5H2O}n, the octahedral V(H2O)2O4 and pyramidal SeO3 building units are linked by V—O—Se bonds to generate ladder‐like chains propagating along the [010] direction. A network of O—H...O hydrogen bonds helps to consolidate the structure. The O atom of the uncoordinated water molecule lies on a crystallographic twofold axis. The title compound has a similar structure to those of the reported phases [VO(OH)(H2O)(SeO3)]4·2H2O and VO(H2O)2(HPO4)·2H2O.  相似文献   

4.
A new organically templated vanadium tellurite, poly[2,2′‐iminodiethanaminium [hexa‐μ2‐oxido‐tetraoxidoditellurium(IV)divanadium(V)] dihydrate], {(C4H15N3)[Te2V2O10]·2H2O}n, features the interconnection of distorted [VO5] trigonal bipyramids by bridging [TeO3] pyramids, leading to a two‐dimensional corrugated anionic layer with an interlayer distance of about 13.47 Å. The interlayer space is occupied by doubly protonated diethylenetriamine cations (H2dien) and guest water molecules. The two terminal amino groups of H2dien are protonated, while the middle amino group, located on a twofold rotation axis, is not protonated. All the three amino groups and water molecules are involved in hydrogen‐bonding interactions. The compound represents a new member in the series (H2am)[(VO2)(TeO3)]2·xH2O, where H2am represents a doubly protonated diamine. Similarities and differences between the structures of members of the series are discussed.  相似文献   

5.
IntroductionSincethepioneerworksofClearfieldandcoworkersinthe 196 0s ,1,2 layeredmetalphosphateshaveattractedmuchattentionduetotheirapplicationsonionex change ,intercalation ,heterogeneouscatalysisandsorp tion .3 7Amongthenumerouslamellarphases ,theproto typical…  相似文献   

6.
In the title compound, disodium cobalt tetrakis­(dihydrogen­phosphate) tetrahydrate, the CoII ion lies on an inversion centre and is octahedrally surrounded by two water molecules and four H2PO4 groups to give a cobalt complex anion of the form [Co(H2PO4)4(OH2)]2?. The three‐dimensional framework results from hydrogen bonding between the anions. The relationship with the structures of Co(H2PO4)2·2H2O and K2CoP4O12·5H2O is discussed.  相似文献   

7.
The title compounds, poly­[bis(2,2′‐bi­pyridine)­bis(μ3‐hydrogen phosphato)­nitratodi‐μ2‐oxo‐dicopper(II)­vanadium dihydrate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·2H2O, (I), and poly­[bis(2,2′‐bi­pyridine)­bis(μ3‐hydrogen phosphato)­nitratodi‐μ2‐oxo‐dicopper(II)­vanadium phospho­ric acid solvate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·H3PO4, (II), were obtained by similar hydro­thermal methods but under different crystallization conditions. The trinuclear entity which serves as the basic unit in both structures presents two independent CuII ions immersed in similar square‐pyramidal N2O3 environments plus an octahedral VO6 core and is organized into a one‐dimensional polymer, which is essentially identical in the two structures. The compounds are stabilized by different solvates, viz. two crystallization water mol­ecules in (I) and a phospho­ric acid mol­ecule in (II), which provide the main structural differences through the diversity of interchain interactions in which they serve as bridges.  相似文献   

8.
郭鸿旭  王庆华  陈晨  梁敏  陈铃 《中国化学》2008,26(4):640-644
水热合成并通过红外、热重、单晶X-射线衍射表征了一个新颖镍配位阳离子修饰的还原型钼磷酸盐,Ni[Mo6O12(OH)3(PO4)(HPO4)3]2][Ni(H2O)2][Ni(H2O)(bipy)2]4·5H2O。单晶X-射线衍射研究表明,两个{Mo6P4}簇单元通过一个镍离子连接形成一个Ni[Mo6P4]2二聚结构单元,其进一步和其他的镍配位阳离子连接成钼磷酸盐一维链状结构。在H2O2存在下的液-固体系中,使用该化合物催化氧化苯甲醛的探针反应结果表明,该化合物具有较高的催化氧化活性。  相似文献   

9.
Two uranyl sulfate hydrates, (H3O)2[(UO2)2(SO4)3(H2O)] · 7H2O (NDUS) and (H3O)2[(UO2)2(SO4)3(H2O)] · 4H2O (NDUS1), and one uranyl selenate‐selenite [C5H6N][(UO2)(SeO4)(HSeO3)] (NDUSe), were obtained and their crystal structures solved. NDUS and NDUSe result from reactions in highly acidic media in the presence of L ‐cystine at 373 K. NDUS crystallized in a closed vial at 278 K after 5 days and NDUSe in an open beaker at 278 K after 2 weeks. NDUS1 was synthesized from aqueous solution at room temperature over the course of a month. NDUS, NDUS1, and NDUSe crystallize in the monoclinic space group P21/n, a = 15.0249(4) Å,b = 9.9320(2) Å, c = 15.6518(4) Å, β = 112.778(1)°, V = 2153.52(9) Å3,Z = 4, the tetragonal space group P43212, a = 10.6111(2) Å,c = 31.644(1) Å, V = 3563.0(2) Å3, Z = 8, and in the monoclinic space group P21/n, a = 8.993(3) Å, b = 13.399(5) Å, c = 10.640(4) Å,β = 108.230(4)°, V = 1217.7(8) Å3, Z = 4, respectively.The structural units of NDUS and NDUS1 are two‐dimensional uranyl sulfate sheets with a U/S ratio of 2/3. The structural unit of NDUSe is a two‐dimensional uranyl selenate‐selenite sheets with a U/Se ratio of 1/2. In‐situ reaction of the L ‐cystine ligands gives two distinct products for the different acids used here. Where sulfuric acid is used, only H3O+ cations are located in the interlayer space, where they balance the charge of the sheets, whereas where selenic acid is used, interlayer C5H6N+ cations result from the cyclization of the carboxyl groups of L ‐cystine, balancing the charge of the sheets.  相似文献   

10.
Single crystals of potassium iron hydrogen phosphate, KFe3(HPO4)2(H2PO4)6 · 4 H2O, were prepared hydrothermally by heating a mixture of Fe2O3, H3PO4 and K2CO3 with a small amount of water. It crystallizes monoclinic, space group C2/c (N° 15 Int. Tab.) with Z = 4 and a = 1701(2), b = 960.4(5), c = 1750(1) pm, β = 90.88(7)°. The crystal structure was solved by using 1716 unique reflections F0 > 4σ(F0) with a final wR2 value of 0.126 (SHELXL-93). The main feature of the crystal structure are layers formed by PO4-tetrahedra around the FeO6-octahedra parallel to (001). K+ and H2O molecules connect these layers. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), Charge Distribution (CHARDI) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound. The existence of hydrogen bonds is confirmed by these calculations.  相似文献   

11.
杂多化合物在催化、医药、材料及光化学等方面具有广泛的应用前景 [1~ 4 ] ,其中钼磷多金属氧酸盐具有优异的氧化催化性能 [5,6 ] .近年来合成的新奇结构的钼磷多金属氧酸盐中已测定结构的有含帽[7,8] 和非帽[9~ 12 ] 系列 .本文利用水热法合成了未见文献报道的结构新颖的夹心型磷钼多金属氧酸盐[( CH3CH2 ) 4N]4 H3O{Na[( HMo2 O5) 3( HPO4 ) ( H2 PO4 ) 3]2 }· ( H2 PO4 ) 2 · 1 0 H2 O,并测定了其晶体结构 .1 实验与晶体结构分析1 .1 仪器与试剂 元素 Na用美国原子吸收分光光度计测定 ;C,H和 N用 Perkin- Elmer 2 4 0…  相似文献   

12.
The title compound, tetrakis­(ethyl­enedi­ammonium) tetra‐μ‐hydrogenphosphato‐di‐μ‐hydro­xo‐ tetra‐μ‐phosphato‐bis­(aqua­cobalt)­hexakis­(oxovanadium) trihydrate, was synthesized hydro­thermally at moderate temperature. The structure consists of diprotonated ethyl­enedi­ammonium cations and layers of the polyanions. The polyanion contains four PO4 tetrahedra and three VO5 square pyramids that are linked through corner‐sharing by alternating P—O—V, which gives rise to a chain. The chains, connected by CoO4(H2O)2 octahedra, form layers, resulting in a two‐dimensional layered structure. The Co—O distances are in the range 1.984 (3)–2.038 (4) Å, the P—O distances 1.508 (3)–1.575 (3) Å and the V—O distances 1.585 (3)–2.010 (3) Å.  相似文献   

13.
The title compound, tri­ammonium cis‐di­aqua‐cis‐dioxo‐trans‐disulfatovanadate 1.5‐hydrate, was obtained by oxidizing VIV to VV in a 2 M sulfuric acid solution of vanadyl­ sulfate and adding ammonium sulfate. Here, the V atom is sandwiched by two sulfate groups by corner‐sharing to form a discrete [VO2(SO4)2(OH2)2]3? anion. The water mol­ecules occupy cis positions in the equatorial plane of the vanadium octahedron.  相似文献   

14.
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   

15.
16.
By adding piperazine to a hydrofluoric and phosphoric acid solution of Manganese(III) fluoride, the fluoride phosphate (pipzH2)[MnF2(HPO4)(H2O)](H2PO4) can be crystallized. Its structure is built by piperazinium(2+) cations, (H2PO4)? anions, and an anionic double‐chain of [HPO4] tetrahedra and [MnO3F2(H2O)] octahedra. The structure is triclinic, space group P , Z = 2, a = 622.97(4), b = 923.46(6), c = 1183.62(7) pm, α = 98.343(6)°, β = 100.747(7)°, γ = 107.642(5)°, R = 0.0289. It is worth noting that a ferrodistortive Jahn‐Teller order is observed with [MnO3F2(H2O)] octahedra strongly elongated along the F–Mn–OH2 axes perpendicular to the chain plane. The structure is stabilized by very strong hydrogen bonds.  相似文献   

17.
The reaction of UO2(NO3)2.6H2O with Co or Cu metal, phosphoric acid, and CsCl under mild hydrothermal conditions results in the formation of Cs2{(UO2)4[Co(H2O)2(HPO4)(PO4)4} (1) or Cs(3+x)[(UO2)3CuH(4-x)(PO4)5].H2O (2). The structure of 1 contains uranium atoms in pentagonal bipyramidal and hexagonal bipyramidal environments. The interaction of the uranyl cations and phosphate anions creates layers in the [ab] plane. The uranyl phosphate layers are joined together by octahedral Co centers wherein the Co is bound by phosphate and two cis water molecules. In addition, the Co ions are also ligated by a uranyl oxo atom. The presence of these octahedral building units stitches the structure together into a three-dimensional framework where void spaces are filled by Cs+ cations. The structure of 2 contains uranium centers in UO6 tetragonal bipyramidal and UO7 pentagonal bipyramidal geometries. The uranyl moieties are bridged by phosphate anions into sinusoidal sheets that extend into the [bc] plane and are linked into a three-dimensional structure by Cu(II). The Cu centers reside in square planar environments. Charge balance is maintained by Cs+ cations. Both the overall structures and the uranyl phosphate layers in 1 and 2 are novel.  相似文献   

18.
Two novel interdigitated metal‐quinolone complexes, namely [Cu2(cfH)2(bptc)(H2O)] · 4H2O ( 1 ) and [Zn2(levofH)2(odpa)] · 5.5H2O ( 2 ) (bptc = 3,3′,4,4′‐benzophenonetetracarboxylate, cfH = ciprofloxacin, odpa = 4,4′‐oxydiphthalate, levofH = levofloxacin) were synthesized hydrothermally and characterized by elemental analyses, IR spectra, UV/Vis spectra, TG analyses, powder X‐ray diffraction, and single‐crystal X‐ray diffraction. Moreover, solid‐state photoluminescence property of compound 2 was also investigated at room temperature. Compound 1 exhibits a novel interdigitated architecture, which is built from 1D chains with side arms. The structure of compound 2 consists of 1D chains with dangling levofloxacin ligands protruding from both sides of the chain, and these chains are interdigitated with each other to generate a interdigitated framework.  相似文献   

19.
Rubidium chromium(III) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­chromium(III)­rubidium(I)], [RbCr(C2O4)2(H2O)2], (I), and dicaesium magnesium dioxalate tetrahydrate [tetra­aqua­bis(μ‐oxalato)­magnesium(II)­dicaesium(I)], [Cs2Mg(C2­O4)2(H2O)4], (II), have layered structures which are new among double‐metal oxalates. In (I), the Rb and Cr atoms lie on sites with imposed 2/m symmetry and the unique water molecule lies on a mirror plane; in (II), the Mg atom lies on a twofold axis. The two non‐equivalent Cr and Mg atoms both show octahedral coordination, with a mean Cr—O distance of 1.966 Å and a mean Mg—O distance of 2.066 Å. Dirubid­ium copper(II) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­copper(II)­dirubidium(I)], [Rb2Cu(C2O4)2(H2O)2], (III), is also layered and is isotypic with the previously described K2‐ and (NH4)2CuII(C2O4)2·2H2O compounds. The two non‐equivalent Cu atoms lie on inversion centres and are both (4+2)‐coordinated. Hydro­gen bonds are medium‐strong to weak in the three compounds. The oxalate groups are slightly non‐planar only in the Cs–Mg compound, (II), and are more distinctly non‐planar in the K–Cu compound, (III).  相似文献   

20.
Single crystals of sodium iron hydrogen phosphate, NaFe(HPO4)(H2PO4)2 · H2O, were prepared hydrothermally by heating a mixture of Fe2O3, H3PO4 and Na2CO3 with a small amount of water. It crystallizes orthorhombic (Pbcn (N° 60), Z = 8, a = 872.91(7), b = 1249.54(8), c = 1894.4(1) pm). The crystal structure was solved by using 1121 unique reflections I > 2σ(I) and refined for a final conventional residual R = 0.039 (188 variables, 25 atoms including hydrogen in the asymmetric unit). The main feature of the crystal structure is a ReO3-like network formed by hydrogenphosphate-, dihydrogenphosphate-groups and Fe O6 octahedra with channels along the [201], [010] and [201] directions. Na+ and H2O molecules are occupying these channels. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound.  相似文献   

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