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1.
Using hydrothermal methods, two manganese arsenates have been synthesized and characterized by single crystal X‐ray diffraction. The products Mn5(AsO4)2(HAsO4)2 ?4H2O ( 1 ) and Mn2AsO4(OH) ( 2 ), the Mn end‐members of the minerals villyaellenite and sarkinite, respectively, have been obtained (crystal data 1 : monoclinic, C2/c, a = 18.109(4), b = 9.332(2), c = 9.809(2) Å, β = 96.172(4)?, Z = 4; 2 : monoclinic, P21/c, a = 10.219(2), b = 13.613(2), c = 12.780(2) Å, β = 108.834(2)?, Z = 16). In both compounds a three‐dimensional framework of edge‐sharing MnO polyhedra is observed. Based on the availability of the all Mn2containing form of villyaellenite ( 1 ), the ordering scheme of the impurity cations of the natural samples could be confirmed. Magnetic susceptibility measurements of 1 indicate the presence of high‐spin Mn2+ ions. The comparison of the data on sarkinite ( 2 ) with the data obtained from the natural sample indicates that the mineral has either a very high Mn content, or an absence of impurity cation ordering.  相似文献   

2.
The crystal structures of Na2Mg3(OH)2(SO4)3 · 4H2O and K2Mg3(OH)2(SO4)3 · 2H2O, were determined from conventional laboratory X‐ray powder diffraction data. Synthesis and crystal growth were made by mixing alkali metal sulfate, magnesium sulfate hydrate, and magnesium oxide with small amounts of water followed by heating at 150 °C. The compounds crystallize in space group Cmc21 (No. 36) with lattice parameters of a = 19.7351(3), b = 7.2228(2), c = 10.0285(2) Å for the sodium and a = 17.9427(2), b = 7.5184(1), c = 9.7945(1) Å for the potassium sample. The crystal structure consists of a linked MgO6–SO4 layered network, where the space between the layers is filled with either potassium (K+) or Na+‐2H2O units. The potassium‐bearing structure is isostructural to K2Co3(OH)2(SO4)3 · 2(H2O). The sodium compound has a similar crystal structure, where the bigger potassium ion is replaced by sodium ions and twice as many water molecules. Geometry optimization of the hydrogen positions were made with an empirical energy code.  相似文献   

3.
The structure of the title compound, potassium trinickel arsenate diarsenate, is built up from corner‐ and edge‐sharing NiO6 octahedra, AsO4 tetrahedra and As2O7 groups, giving rise to a polyhedral connectivity which produces large tunnels running along the crystallographic [010] direction. The K+ cations are located within these tunnels.  相似文献   

4.
Crystals of the title hydrated rubidium gallium phosphate, rubidium aqua‐μ3‐hydroxo‐di‐μ‐phosphato‐digallium hydrate, were synthesized hydro­thermally at 453 K under autogenous pressure. The solid crystallizes in the monoclinic system and its structure was determined from single‐crystal X‐ray diffraction analysis. It is similar to dihydrated gallium phosphate, GaPO4·2H2O, which is isostructural with the mineral leucophosphite. The structure is built up from a three‐dimensional anionic framework composed of corner‐linked octameric Ga4(PO4)4(OH)2(H2O)2 units. The Ga atom is in an octahedral coordination. Connection of the Ga4P4 species generates eight‐ring channels, in which are encapsulated the Rb+ cations and water mol­ecules.  相似文献   

5.
Crystal Structures of Sr(OH)2 · H2O, Ba(OH)2 · H2O (o.-rh. and mon.), and Ba(OH)2 · 3 H2O The crystal structures of Ba(OH)2 · 3 H2O (Pnma, Z = 4), γ-Ba(OH)2 · H2O (P21/m, Z = 2) and the isotypic Sr(OH)2 · H2O and β-Ba(OH)2 · H2O (Pmc21, Z = 2) were determined using X-ray single crystal data. Ba(OH)2 · 3 H2O and Ba(OH)2 · H2O mon. crystallize in hitherto unknown structure types. The structure of Ba(OH)2 · H2O mon. is strongly related to that of rare earth hydroxides M(OH)3 with space group P63/m (super group of P21/m). The metal-oxygen distances are significantly shorter for OH? ions (mean Ba—O bond lengths of all hydroxides under investigation 278.1 pm) than for H2O molecules (289.9 pm). Corresponding to other hydrates of ionic hydroxides, the water molecules form strong hydrogen bonds to adjacent OH? ions whereas the hydroxide are not H-bonded.  相似文献   

6.
Te(OH)6 · 2Na3P3O9 · 6H2O, is hexagonal (P63/m) with a = 11,67(1), c = 12,12(1) Å, Z = 2 and Dx = 2,225 g/cm3. Te(OH)6 · K3P3O9 · 2H2O, is monoklin (P21/c) with a = 19,61(5), b = 7,456(1), c = 14,84(6) Å, = 108,01(4), Z = 4 and Dx = 2,506 g/cm3. Both compounds are the first examples of phosphate tellurates in which the anion phosphate is condensed to the ring anion P3O9. As in phosphate tellurates already described the phosphate groups are independent of the TeO6 octahedra.  相似文献   

7.
Crystal Structure of SrZn(OH)4 · H2O Colorless crystals of SrZn(OH)4 · H2O are obtained by electrochemical oxidation of Zn in a zinc/iron pair in an aqueous ammonia solution saturated with strontium hydroxide. The X-ray crystal structure determination was now successful including all hydrogen positions: P1 , Z = 2, a = 6.244(1) Å, b = 6.3000(8) Å, c = 7.701(1) Å, α = 90.59(1)°, β = 112.56(2)°, γ = 108.66(2)°, N(F ≥ 3σF) = 1967, N(Var.) = 84, R/Rw = 0.020/0.024. In SrZn(OH)4 · H2O Zn2+ is tetrahedrally coordinated by four OH? -ions while Sr2+ has 6 OH? and one H2O as neighbours. The polyhedra around Sr2+ are connected to chains which are linked three-dimensionally by isolated tetrahedra [Zn(OH)4]. Hydrogen bonds between H2O as donor and OH? are characterized by raman spectroscopy.  相似文献   

8.
Crystal Structure of Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O The crystall structures of the isostructural halates Sr(BrO3)2 · H2O, Ba(BrO3)2 · H2O, Ba(IO3)2 · H2O, Pb(ClO3)2 · H2O, and Pb(BrO3)2 · H2O were determined using X-ray single crystal data (monoclinic space group C2/c? C, Z = 4), The mean bond lengths and bond angles of the halate ions in the Ba(ClO3)2 · 1 H2O-type compounds, which correspond to those of other halates, are Cl? O, 149.0, Br? O, 165.9, I? O, 180.2 pm, ClO3?, 106.4, BrO3?, 104.0, and IO3?, 99.6°. The structure data obtained are discussed in terms of possible orientational disorder of the water molecules, strengths of the hydrogen bonds, influence of the lead ions on the structure, and site group distortion of the halate ions.  相似文献   

9.
In the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)2 · MgSO4 · 8H2O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)2‐MgSO4‐H2O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) Å3]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH2)2(OH)4 octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO4 tetrahedra and interstitial water molecules separate the stacks of parallel double chains.  相似文献   

10.
Light‐yellow single crystals of the mixed‐valent mercury‐rich basic nitrate Hg8O4(OH)(NO3)5 were obtained as a by‐product at 85 °C from a melt consisting of stoichiometric amounts of (HgI2)(NO3)2·2H2O and HgII(OH)(NO3). The title compound, represented by the more detailed formula HgI2(NO3)2·HgII(OH)(NO3)·HgII(NO3)2·4HgIIO, exhibits a new structure type (monoclinic, C2/c, Z = 4, a = 6.7708(7), b = 11.6692(11), c = 24.492(2) Å, β = 96.851(2)°, 2920 structure factors, 178 parameters, R1[F2 > 2σ(F2)] = 0.0316) and is made up of almost linear [O‐HgII‐O] and [O‐HgI‐HgI‐O] building blocks with typical HgII‐O distances around 2.06Å and a HgI‐O distance of 2.13Å. The Hg22+ dumbbell exhibits a characteristic Hg‐Hg distance of 2.5079(7) Å. The different types of mercury‐oxygen units form a complex three‐dimensional network exhibiting large cavities which are occupied by the nitrate groups. The NO3? anions show only weak interactions between the nitrate oxygen atoms and the mercury atoms which are at distances > 2.6Å from one another. One of the three crystallographically independent nitrate groups is disordered.  相似文献   

11.
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   

12.
The title saccharinate complexes, aqua[1,2‐benzisothiazol‐3(2H)‐onato 1,1‐dioxide‐N]bis(1,10‐phenanthroline‐N,N′)man­ganese(II) 1,2‐benz­isothia­zol‐3(2H)‐onate 1,1‐dioxide,[Mn(C7H4NO3S)(C12H8N2)2(H2O)](C7H4NO3S), and aqua[1,2‐benz­iso­thiazol‐3(2H)‐onato 1,1‐dioxide‐N]­bis­(2,2′‐bi­pyri­dine‐N,N′)­cobalt(II) 1,2‐benz­iso­thia­zol‐3(2H)‐onate 1,1‐di­oxide, [Co­(C7H4NO3S)­(C10H8N2)2­(H2O)]­(C7H4NO3S), have been prepared and their crystal structures determined at 150 K. The structure of the manganese complex consists of repeated alternating [Mn(phen)2(sac)(H2O)]+ cations and non‐coordinated saccharinate anions. The water molecule, bound to manganese as part of a slightly distorted octahedral arrangement, is hydrogen bonded to an O atom of the SO2 group in the saccharinate counter‐ion. In contrast, the cobalt complex has one pseudo‐octahedral [Co(bipy)2(sac)(H2O)]+ cation, with the cobalt‐bound water molecule hydrogen bonded to the N atom of the accompanying free saccharinate anion.  相似文献   

13.
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15.
The crystal structure of the title compound, nona­ammonium (arsenic decatungstido)(arsenic heptatungstido)­di­aqua‐μ‐hydroxo‐(hydroxy­arsenido)­di­zir­conium hexa­cosa­hydrate, which was ob­tained from the reaction of [NaAs4W40O140]27− with ZrIV, has been determined. The anionic complex consists of two hydroxyl‐bridged seven‐coordinate capped trigonal‐prismatic zirconium ions, which are bonded to an [AsW10O36]9− anion and to an [AsW7O28]11− anion that has two {AsOH}2+ capping units. The asymmetric unit contains half of the complex, with one crystallographically independent Zr atom. Crystallographic m symmetry imposed by the monoclinic C2/m space group gives rise to the asymmetric unit comprising half of the complex with one crystallographically independent Zr atom.  相似文献   

16.
在水乙醇混合溶剂中,首次得到了2-羰基丙酸水杨酰腙、1,10-菲啰啉与硝酸钆形成的配合物[Gd(C10H9N2O4)(C10H8N2O4)(H2O)3]2·phen·4H2O,并测试了其单晶结构。该配合物属三斜晶系,空间群为P-1。每个配合物分子中有两个九配位的钆的结构单元,每个钆离子与两个三齿配体2-羰基丙酸水杨酰腙(分别以负一价和负二价形式)和三个水分子配位。每个钆单元在空间呈扭曲的单帽四方反棱柱。同时还有一个游离的1,10-菲啰啉存在于晶格中,通过氢键与配位水作用。生物活性试验表明该配合物对三种病原菌有一定的抑菌活性。  相似文献   

17.
Dicaesium divanadium trioxide phosphate hydrogenphosphate, Cs2V2O3(PO4)(HPO4), (I), and dicaesium tris[oxidovanadate(IV)] hydrogenphosphate dihydrate, Cs2[(VO)3(HPO4)4(H2O)]·H2O, (II), crystallize in the monoclinic system with all atoms in general positions. The structures of the two compounds are built up from VO6 octahedra and PO4 tetrahedra. In (I), infinite chains of corner‐sharing VO6 octahedra are connected to V2O10 dimers by phosphate and hydrogenphosphate groups, while in (II) three vanadium octahedra share vertices leading to V3O15(H2O) trimers separated by hydrogenphosphate groups. Both structures show three‐dimensional frameworks with tunnels in which Cs+ cations are located.  相似文献   

18.
19.
Thermal Decomposition of Afwillite Ca3(SiO3OH)2 · 2 H2O Using the molybdate method [1], infrared, Raman, and high resolution solid state 1H and 29Si NMR spectroscopy two intermediate phases can be identified in the process of dehydration of afwillite: At temperatures of 250 to 300°C a non-crystalline phase is formed mainly (about 80 to 90% referred to Si) with a structure similar to mineral killalaite Ca3OH(Si2O6OH) [2] and phase F [3]. Between 300 and 500°C this compound is converted to a non-crystalline kilchoanite-like phase γ-Ca2SiO4 · Ca4Si3O10 [4], consisting of ordered γ-Ca2SiO4 and disordered trisilicate layers. By a side reaction polysilicate (about 10 to 20% referred to Si) is formed.  相似文献   

20.
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