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1.
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   

2.
3.
On the Coordination of Al in the Calcium Aluminate Hydrates 2 CaO · Al2O3 · 8 H2O and CaO · Al2O3 · 10 H2O By investigations with high-resolution 27Al-NMR in solids it is shown that in the compound 2 CaO · Al2O3 · 8 H2O the Al merely exist in octahedral coordination. According to this and considering its structural relationship with 4 CaO · Al2O3 · 19 H2O the dicalcium aluminate hydrate is proposed to be formulated as [Ca2Al(OH)6][Al(OH)3 (H2O)3]OH. Likewise for the compound CaO · Al2O3 · 10 H2O the octahedral coordination of the Al is proved by 27Al-NMR. This result corresponds with literature according to which a constitution as cyclohexaaluminate Ca3[Al6(OH)24] · 18 H2O is proposed.  相似文献   

4.
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   

5.
On the Compound BaO · Al2O3 · 7 H2O On the basis of investigations using 27Al, 1H NMR, IR and thermoanalytical methods for the compound BaO · Al2O3 · 7 H2O a constitution as Ban[Al2(OH)8]n · 3n H2O with condensed AlO6 groups, sharing edges, is proposed. Relations between the Ba/Al ratio and the constitution of anions of barium aluminate hydrates are discussed.  相似文献   

6.
On the Alkali Selenoarsenates(III) KAsSe3 · H2O, RbAsSe3 · 1/2 H2O, and CsAsSe3 · 1/2 H2O The alkali selenoarsenates(III) KAsSe3 · H2O, RbAsSe3 · 1/2 H2O, and CsAsSe3 · 1/2 H2O have been prepared by hydrothermal reaction of the respective alkali carbonate with As2Se3 at a temperature of 135°C. Their X-ray structural analyses demonstrated that the compounds contain polyselenoarsenate(III) anions (AsSe3?)n, in wich the basic units are ψ-AsSe3 tetrahedra, which are linked together through Se? Se bonds into infinite zweier single chains. The Rb and Cs salts are isotypic.  相似文献   

7.
K2TiSi3O9·H2O     
Single crystals of dipotassium titanium trisilicate hydrate were synthesized and the crystal structure was refined using data from single‐crystal X‐ray diffraction. The structure is a three‐dimensional mixed framework and contains channels formed by six‐ and eight‐membered rings. K+ ions and water mol­ecules are located in the channels.  相似文献   

8.
The title compound, namely octa­aqua­ytterbium(III) aqua­nona­chloro­tricadmate(II) hexa­hydrate, [Yb(H2O)8][Cd3Cl9(H2O)]·6H2O, was prepared by evaporation at 278 K from an aqueous solution of the ternary system YbCl3–CdCl2–H2O and was characterized by elemental chemical analysis and by X‐ray powder and single‐crystal diffraction studies. The crystal structure can be viewed as being built from layers of double chains of CdCl6 and CdCl5(H2O) octahedra separated by antiprismatic [Yb(H2O)8]3+ cations. The stabilization of the structure is ensured by O—H⋯O and O—H⋯Cl hydrogen bonds. A comparison with the structures of SrCd2Cl6·8H2O and CeCd4Cl11·13H2O is presented.  相似文献   

9.
In contrast to former morphological studies, the results presented here show that calcium(II) thio­sulfate hexahydrate, CaS2O3·6H2O, crystallizes centrosymmetrically in the pinacoidal class (point group ). The structure is characterized by chains, parallel to [100], of alternating S2O3 and Ca(H2O)6O2 groups sharing common O atoms. The composition of each chain link is [Ca(H2O)6(S2O3)]. The geometry is analysed and compared in detail with the structural features of monoclinic strontium(II) thio­sulfate pentahydrate, SrS2O3·5H2O, which forms layers, parallel to (100), of alternating S2O3 and Sr(H2O)4O5 groups connected via common O atoms and O–O edges. Each layer contains [Sr(H2O)3O(S2O3)] as the unique repeat unit.  相似文献   

10.
The calcium salts Ca2P2O6 · 2H2O ( 1 ) and [Ca(H2O)3(H2P2O6)] · 0.5(C12H24O6) · H2O ( 2 ) were prepared and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pbca and compound 2 in the monoclinic space group P21/n. The crystal structure of compound 1 consists of chains of edge‐sharing [CaO7] polyhedra linked by hypodiphosphate(IV) anions to form a three‐dimensional network. The crystal structure of compound 2 consists of alternated layers of crown ether and water molecules and respective ionic units. Within the layers of ionic units the Ca2+ cations are octahedrally coordinated by three monodentate dihydrogenhypodiphosphate(IV) anions and three water molecules. The IR/Raman spectra of the title compounds were recorded and interpreted, especially with respect to the [P2O6]4– and [H2P2O6]2– groups. The phase purity of 2 was verified by powder diffraction measurements.  相似文献   

11.
Water‐rich aluminium halide hydrate structures are not known in the literature. The highest known water content per Al atom is nine for the perchlorate and fluoride. The nonahydrate of aluminium bromide, stable pentadecahydrates of aluminium chloride, bromide and iodide, and a metastable heptadecahydrate of the iodide have now been crystallized from low‐temperature solutions. The structures of these hydrates were determined and are discussed in terms of the development of cation hydration spheres. The pentadecahydrate of the chloride and bromide are isostructural. In AlI3·15H2O, half of the Al3+ cations are surrounded by two complete hydration spheres, with six H2O in the primary and 12 in the secondary. For the heptadecahydrate of aluminium iodide, this hydration was found for every Al3+.  相似文献   

12.
On the Preparation and Constitution of the Compound 3 CaO · 3 GeO2 · H2O In the temperature range from 100–∽450°C it is possible to prepare under hydrothermal conditions from equimolar mixtures of CaO and GeO2 the compound 3 CaGeO3 · H2O. By n.m.r. measurements of the solid compound it is shown, that there are only OH groups and no molecular water. It seems to be probable that this compound is a trigermanate of the formula Ca3H2 [Ge3O10].  相似文献   

13.
刘志宏  赵莉  胡满成 《中国化学》2003,21(12):1569-1572
Introduction   2MgO·B2 O3(Mg2 B2 O5)and 2MgO·B2 O3·H2 Omightbepreparedaswhiskermaterials .12MgO·B2 O3·H2 OnamedszaibelyiteisamagnesiumboratemineralwithastructuralformulaofMg2 [B2 O4 (OH) 2 ].2 Itisdifficulttosynthesizethiscompoundinthelaboratory .Recently ,weobtainedasimilarcompound 2MgO·B2 O3·1 5H2 Owhenwetriedtopreparewhiskerof 2MgO·B2 O3·H2 Obythephasetransformationof 2MgO·2B2 O3·MgCl2 ·14H2 OinH3BO3solutionunderhydrothermalcondition .Itishope fultopreparewh…  相似文献   

14.
The crystal structures of tricopper decavanadate tetracosa­hydrate, (I), and copper tetra­sodium decavanadate tricosa­hydrate, (II), have been determined by single‐crystal X‐ray diffraction. Both compounds exhibit a catenary structure consisting of [V10O28]6− anions linked by Cu2+ cations in (I) or by Na+ cations in (II). Compound (II) also contains a polymeric linear array of edge‐sharing [Na(OH2)6]+ and [Cu(OH2)6]2+ octahedra. In both compounds, the [V10O28]6− ions lie about inversion centres and the Cu2+ ions in (I) also lie about inversion centers.  相似文献   

15.
The crystal structures of dimagnesium disodium decavanadate icosahydrate, Mg2Na2V10O28·20H2O, (I), and trimagnesium decavanadate octacosahydrate, Mg3V10O28·28H2O, (II), have been determined by single‐crystal X‐ray diffraction. They crystallize with monoclinic (C2/c) and triclinic () symmetry, respectively. All the Mg2+ cations in (I) and (II) are octahedrally coordinated by six water mol­ecules. The Na+ cations in (I) are coordinated by three water mol­ecules and three O atoms of the decavanadate anions, and link the latter into a three‐dimensional network. The decavanadate anions in (II) are not linked to one another.  相似文献   

16.
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   

17.
Crystal Structure of the Magnesium Octachlorotrimercurate(II)-hexahydrate MgHg3Cl8 · 6 H2O Colourless crystals of MgHg3Cl8 · 6 H2O were obtained by crystallization from aqueous solutions of MgCl2 and HgCl2. There were no indications of the existence of the reported compounds MgHgCl4 · 6 H2O and MgHg2Cl6 · 6 H2O. The crystal structure of the triclinic MgHg3Cl8 · 6 H2O consists of linear pseudo HgCl2 molecules, binuclear Hg2Cl6 anions and octahedral Mg(OH2)6 kations.  相似文献   

18.
刘志宏  高世扬  胡满成  夏树屏 《中国化学》2002,20(12):1519-1522
IntroductionTherearemanykindsofmagnesiumborates ,bothnaturalandsynthetic .Aboratedoublesalt (2MgO·2B2 O3 ·MgCl2 · 14H2 O)namedchloropinnoitewasob tainedfromthenaturalconcentratedsaltlakebrine .1Inordertofindtheformingrelationbetweenthedoublesaltandmagnesium bora…  相似文献   

19.
Alkaline Earth Fluoromanganates(III): BaMnF5 · H2O and SrMnF5 · H2O Solid BaF2 or SrF2 forms with solutions of Mn3+ in aqueous hydrofluoric acid precipitates of hitherto unknown BaMnF5 · H2 and SrMnF5 · H2O respectively. X-ray structure determination on single crystals of both isotypic compounds (space group P21/m, Z = 2; BaMnF5 · H2O: a = 537.0(3), b = 817.2(2), c = 628.0(4) pm β = 111.17(5)°, Rw = 0.035 for 1403 reflections; SrMnF5 · H2O: a = 510.8(1), b = 792.0(2), c = 610.6(1) pm, β = 110.24(1)° Rw = 0.068 for 539 reflections) reveal pure [MnF6]3? octahedra connected with each other to infinite chains by sharing trans corners. The H2O molecules are coordinated to the alkaline earth ions only and form weak O? H…F hydrogen bonds. The pronounced weakening of the Mn? F bonds within the chain direction (Mn? F 2X 212.7(1)/210.8(5) pm, 2X 183.8(3)/181.8(9) pm, 2X 186.9(2)/187.2(8) pm) may be due by halves to the Jahn-Teller-effect as can be deduced by bond valence calculations.  相似文献   

20.
IntroductionMononuclear ,dinuclearandpolymerictypesofcrys talstructuresforlanthanidecomplexeswithbenzoicacidanditsderivativeshavebeenobtainedbecauseofthevari ationofbridgingformsforcarboxylategroupandcoordina tionabilityofdiammineligands ,suchas 1,10 phena…  相似文献   

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