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1.
《Materials Research Bulletin》1987,22(11):1483-1491
Single crystal of [Y(H2O)3]2 (C6Br2O4)3·6H2O and [Y(H2O)3]2 (C6Cl2O4)3·6.6H2O were grown in aqueous silicagel. The compounds are in principle isostructural. In Y chloranilate one additional water site is occupied as verified by X-ray single crystal structure analysis. Y3+ is nine-coordinated by three water molecules and six oxygen atoms of the bischelating (C6X2O4)2− ions (XCl, Br). The coordination polyhedron is an only slightly distorted tri-capped trigonal prism. The connection of Y3+ with the dianions leads to infinite, corrugated layers. The layer stacking yields cage-like cavities in which water molecules are accomodated. Hydrogen bonds interlink adjacent layers. Further hydrogen bonds involve the entrapped water molecules. DSC measurements indicated a complicated dehydration process which caused right at the start destruction of the single crystals.  相似文献   

2.
NaMg(H2O)2[BP2O8]·H2O was prepared by hydrothermal synthesis and was characterized by X-ray powder difraction and IR method. The title compound was synthesized from MgCl2·6H2O, NaBO3·4H2O, and (NH4)2HPO4 with variable molar ratios using hydrothermal method by heating at 165 °C for 3 days. The X-ray powder diffraction data was indexed in hexagonal system, the unit cell parameters were found to be as a = 9.428, c = 15.82 Å, Z = 4 and the space group is P6122. It is isostructural with MlMll(H2O)[BP2O8] type compounds where Ml = Na, K; Mll = Mg, Mn, Fe, Co, Ni and Zn. In addition NH4Mg(H2O)2[BP2O8]·H2O was also synthesized the first time in this research. Its unit cell parameters and hkl values were in good agreement with the sodium magnesium compound. The unit cell parameters are a = 9.529, c = 15.736 Å. The indexed X-ray powder diffraction data of both compounds which were not reported in the literature is presented in this work. The IR data of NaMg(H2O)2[BP2O8]·H2O is also reported.  相似文献   

3.
《晶体工程》2000,3(1):1-10
The two cadmium cyanide complexes Cd(CN)2 (4,4'–bipy)0.5 (1) and [Cd(2,2'–bipy)(CN)2]3·H2O (2) show infinite 3D and 2D [Cd(CN)2]n framework structures, respectively. The cadmium cyanide framework in 1 is topologically the same as the cristobalite-like [Cd(CN)2]n framework but is severely distorted. A 4,4'–bipyridine molecule is trapped in each ‘supercage’ which is formed from two adjacent adamantane-like cadmium cyanide cages. In 2, the bidentate 2,2'–bipyridine ligands are coordinated to cadmium centers to prevent expansion of the 2D cadmium cyanide framework into a 3D framework.  相似文献   

4.
《晶体工程》2000,3(4):237-250
Two novel materials, [HMTA-H··H2O] [HMTA-CH2OH] [H3V10O28[Na(H2O)4}]·4H2O, 1 and [Na2(H2O)10][H3V10O28[Na(H2O)2}]·3H2O, 2 containing decavanadate clusters interconnected through hydrated sodium cations forming 1D molecular chains and 2D molecular arrays have been self-assembled from acidified, aqueous vanadate solution in the presence of organic bases, hexamethylenetetramine and 1,3,5-triazine respectively.  相似文献   

5.
《晶体工程》1999,2(2-3):91-100
We have observed an unusual example of cobalt-mediated cyclization of 4-pyridinecarboxaldehyde and 2-nitroaniline to afford 2-(4-pyridyl)benzimidazole under hydro(solvo)thermal conditions. Reaction of Co(NO3)2·6H2O with 4-pyridinecarboxaldehyde and 2-nitroaniline in ethanol at 120°C gave a cobalt(II) coordination compound, Co[2-(4-pyridyl)benzimidazole]2(H2O)2(NO3)2, 1. In contrast, when the hydro(solvo)thermal reaction was carried out between Co(NO3)2·6H2O and isonicotinic acid in the presence of 2-nitroaniline at 110°C, a one-dimensional Co(II) coordination polymer with the formula of [Co(isonicotinate)(4-pyridiniumcarboxylate)(H2O)(NO3)], 2, resulted. The X-ray single crystal structures of both 1 and 2 are described. Interestingly, the isonicotinic acid in 2 exists as a 4-pyridiniumcarboxylate tautomer, and the pyridinium hydrogen atom forms a very strong hydrogen bond to the carboxylate oxygen of the 4-pyridiniumcarboxylate on an adjacent metal center. 1 forms a three-dimensional polymeric network through hydrogen bonding interactions, while 2 exists as a 2-D bilayer polymeric network through hydrogen bonding interactions.  相似文献   

6.
The compound Cs3[UO2(CH3COO)3]2(NCS)·H2O (I) was synthesized and studied by IR spectroscopy and single crystal X-ray diffraction. Compound I crystallizes in the monoclinic system with the following unit cell parameters: a = 7.8286(9), b = 19.892(2), c = 20.050(2) Å, β = 94.527(2)°, space group P21/c, Z = 4, R = 0.0387. The uranium-containing structural units in crystals of I are mononuclear complexes [UO2(CH3COO)3]? belonging to crystal-chemical group AB 3 01 (A = UO 2 2+ , B01 = CH3COO?) of uranyl complexes.  相似文献   

7.
Uranosilicates of the general formula MI I[HSiUO6]2·2H2O (MI I = Sr, Ba) were prepared by hydrothermal synthesis. Previously unknown intermediate crystal hydrates were separated and studied by X-ray diffraction (XRD), IR spectroscopy, and thermal analysis. Polymorphic transitions -Sr[HSiUO6]2 -Sr[HSiUO6]2 and -Ba[HSiUO6]2 -Ba[HSiUO6]2 were revealed at 700 and 780°C, respectively.  相似文献   

8.
Actinide(VII) salts Rb3[NpO4(OH)2]·3H2O (I) and Rb3[PuO4(OH)2]·3H2O (II) were prepared as single crystals and examined by X-ray diffraction. The compounds are isostructural and crystallize in the monoclinic system, space group C2/c, Z = 4; unit cell parameters: a = 12.1544(3), b = 10.9942(2), c = 7.789(2) ?, ?? = 91.0930(11)° for I and a = 12.1254(3), b = 10.9506(2), c = 7.7699(2) ?, ?? = 90.8253(12)° for II. The main structural elements of I and II are centrosymmetrical anions [AnO4(OH)2]3? forming together with water molecules, owing to strong hydrogen bonding, chains oriented along [101]. In [AnO4(OH)2]3? anions, the central An(VII) atom has a tetragonal-bipyramidal oxygen surrounding. The An-O(OH) interatomic distances decrease in going from I to II owing to actinide contraction by a factor of ??2 more strongly than the An-O bond lengths in the equatorial planes of the bipyramids. The previously studied structure of Cs3[NpO4(OH)2]·3H2O (III) was refined.  相似文献   

9.
Radiochemistry - Actinide(VI) complexes with succinate anions [PuO2(succ)(H2O)] and Cs2[(AnO2)2(succ)3]·H2O (An = U, Np, Pu), where succ = [C4H4O4]2 ?, were synthesized and studied by...  相似文献   

10.
通过采用水热合成法得到了二种具有纳米筛孔的氧簇化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(Mo O4)2](Ⅱ).晶体(Ⅰ)属于单斜晶系,空间群为C2/m,晶胞参数为:a=9.5450(17),b=6.4381(9),c=0.76405(12)nm;β=116.128(4),Z=2,R1=0.0219,Rw=0.0756.晶体(Ⅱ)属于正交晶系,空间群为Pnma,晶胞参数为:a=1.4782(3),b=0.56774(11),c=0.87653(18)nm;Z=4,R1=0.0212,Rw=0.0513.  相似文献   

11.
Crystals of a new hybrid compound C8H12N+, HSO4?·H2O were synthesized in aqueous solution and characterized by X-ray diffraction and IR absorption spectroscopy. This compound crystallizes in the orthorhombic non-centrosymmetrical space group P212121 and an unit cell with a = 5.74(2) Å, b = 9.17(2) Å, c = 21.34(4) Å, V = 1124(6) Å3, and Z = 4. Its crystal structure is a packing of alternated inorganic and organic layers parallel to (a,b) planes. The different components are connected by a bi-dimensional network of strong OH…O and NH…O hydrogen bonds. Then, in order to detect phase transitions and watch changes in the conductivity behaviour, investigations by DTA–TG and differential scanning calorimetry (DSC) and electrical conductivity measurements were carried out.  相似文献   

12.
Synthesis and the results of IR and single crystal X-ray diffraction study of Na4(UO2)4(i-C4H9COO)11·(NO3)·3H2O are reported. The crystals are monoclinic; the unit cell parameters at 100 K are as follows: a = 13.697(2), b = 20.285(3), c = 15.991(3) Å, β = 103.760(3)°, space group P21, Z = 2, R = 0.0650. The uraniumcontaining structural units are mononuclear moieties [UO2(i-C4H9COO)3]? and [UO2(NO3)(i-C4H9COO)2]?, belonging to crystal-chemical group AB 3 01 (A = UO 2 2+ , B01 = i-C4H9COO? and NO 3 ? ) of uranyl complexes. The IR data are consistent with the results of the single crystal X-ray diffraction study. The influence of the carboxylate ligand volume on the structure of Na[UO2L3nH2O crystals (L = acetate, n-butyrate, isovalerate ion) is analyzed.  相似文献   

13.
The mechanochemical reaction of C60 and Bi(NO3)3·5H2O was performed under ball-milling condition. The product was well characterized by spectroscopic methods such as IR, Raman, UV-vis, 13C NMR, as well as elemental analysis method. The spectroscopic investigation indicates that some hydroxyl and nitro groups are attached to the C60 and no profound structural changes occur for the C60 cage in the product. The elemental analysis gives an average composition of C60(NO2)2(OH)21 for the product. A possible mechanism is suggested for the reaction.  相似文献   

14.
An X-ray diffraction study of Rb[UO2(SeO4)F]·H2O (I) was performed. The compound crystallizes in the rhombic system with the following unit cell parameters: a = 8.4753(6), b = 13.5234(9), c = 13.5296(9) Å, space group Pnma, Z = 8, V = 1550.7(2) Å3; R = 0.0248. The principal structural units of crystals of I are [UO2(SeO4)F]? layers belonging to crystal-chemical group AT3M2 (A = UO 2 2+ , T3 = SeO 4 2? , M2 = F?) of uranyl complexes. The uranium-containing layered units are combined via electrostatic interaction with Rb cations and via a system of hydrogen bonds involving outer-sphere water molecules.  相似文献   

15.
Products of decomposition of the UO2(NO3)2·6H2O + Fe(NO3)3·9H2O mixture under the action of microwave radiation (MWR) were studied by thermal gravimetric, X-ray phase, and chemical analyses. The results obtained were compared to the published data for various U and Fe compounds. The final products of decomposition of the UO2(NO3)2·6H2O + Fe(NO3)3·9H2O mixture under the action of MWR for 3?C5 min (the maximal temperature of the process, equal to 140?C150°, is attained within 2?C3 min of irradiation), apart from gaseous products, are UO2(OH)NO3, UO3, and Fe2O3. The action of MWR on the UO2(NO3)2·6H2O + Fe(NO3)3·9H2O mixture under the examined conditions does not lead to the formation of uranyl ferrite.  相似文献   

16.
《晶体工程》1999,2(1):37-45
The synthesis and crystal structures of [M(4,4′-bipyridine)2(NO3)2]·3naphthalene (M = Co, 1·3naphthalene; Ni, 2·3naphthalene) are reported. 1·3naphthalene and 2·3naphthalene are isostructural and represent rare examples of interpenetrating planar networks that are chemically and topologically different. It appears that the networks coexist because the (4,4) topology of the cobalt and nickel square grids is complementary to the (6,3) topology of the naphthalene honeycomb network, resulting in an inclined interpenetrated 3D architecture. This observation is discussed in the context of rational design strategies for hybrid solids.  相似文献   

17.
A zinc vanadate with the formula Zn3(VO4)2·3H2O was synthesized by hydrothermal reaction of a gel of composition [(CH3CO2)2Zn·2H2O] : 0.5V2O5: 0.4 [1,3-diaminepropane] : 1.5 NaOH : 114 H2O, held at 170°C for 24 hours. The structure was determined ab initio by means of the EXPO direct methods program and refined with GSAS. The pale yellow solid crystallizes in the hexagonal space group P-6 with a= 6.07877(8), c= 7.1827(2) Å. The structure consists of vanadium tetrahedra bonded to distorted octahedral zinc atoms to create one dimensional columnar passageways for molecules. Though occupied by water in the as synthesized form, the passages could host other small molecules.  相似文献   

18.
Precipitation of salts M3[NpO4(OH)2nH2O (M = Na, K, Rb, Cs) from concentrated alkali solutions at low temperatures (about ?10°C) was studied. From solutions with [OH?] > 9.5 M, these compounds are isolated as coarse black crystals in high yield without impurity of other phases. The K, Rb, and Cs salts crystallize in the form of the previously studied compounds K3[NpO4(OH)2]·2H2O and M3[NpO4(OH)2]·3H2O (M = Rb, Cs). In the case of Na, a new hydrate Na3[NpO4(OH)2]·6H2O was obtained, and its crystal structure was determined. Crystals of the hexahydrate consist of centrosymmetrical tetragonal-bipyramidal anions [NpO4(OH)2]3?, crystallographically independent Na(1) and Na(2) cations, and water molecules. The coordination surrounding of the Np atom is characterized by noticeable difference (Δ = 0.0203 Å) in the Np-O bond lengths in the equatorial plane of the bipyramid. The [NpO4(OH)2]3? anions are combined with the Na(2) cations to form infinite chains [Na(2)NpO4(OH)2(H2O)2]2? in such a manner that the lateral edges of the anion are simultaneously the lateral edges of the Na(2) coordination polyhedron. Incorporation of one of the two crystallographically independent O atoms of the NpO4 group into the Na(2) coordination surrounding is responsible for a noticeable difference in the Np-O bond lengths in the equator of the [NpO4(OH)2]3? anion. The types of hydrogen bonding in the structures of Na3[NpO4(OH)2nH2O (n = 0, 2, 4, 6) are compared.  相似文献   

19.
《晶体工程》1999,2(2-3):171-179
The reaction of an aqueous solution of lithium vanadate with hydrazinium sulfate results in a dark-colored solution that reacts with magnesium sulfate heptahydrate, calcium sulfate dihydrate, and manganese(II) chloride tetrahydrate to yield single crystals of (N2H5)2[M3(H2O)12V18O42(EO4)]·24H2O (M = Mg, Ca) and Li6[Mn3(H2O)12V18O42(EO4)]·24H2O (E = V, S), respectively. The crystal structures of the new solids consist of interpenetrating three-dimensional networks of {V18O42(EO4)} clusters interlinked via bridging {M(H2O)4} (M = Mg, Ca, Mn) groups. The voids in these structures are occupied by lattice water and ion exchangeable cations.  相似文献   

20.
Rare earth co-permeation of (N H4)3 [CrMo6 O24 H6]·7H2O was reported and the conductivity of (N H4)3 [CrMo6O24 H6]was improved by 6.734× 109 times. X-ray fluorescence spectrometry (XRF), thermogravimetry-differential thermal sample. Experimental results showed that Nd could be permeated into the body of this sample and the XRD patterns showed great difference between (NH4)3[CrMo6O24H6]·7H2O and permeated sample. The structure of (NH4)3[CrMo6O24H6]·7H2O was destroyed and new compound MoN perhaps formed.  相似文献   

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