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1.
Three new alkali metal transition metal sulfate‐oxalates, RbFe(SO4)(C2O4)0.5 · H2O and CsM(SO4)(C2O4)0.5 · H2O (M = Mn, Fe) were prepared through hydrothermal reactions and characterized by single‐crystal X‐ray diffraction, solid state UV/Vis/NIR diffuse reflectance spectroscopy, infrared spectra, thermogravimetric analysis, and powder X‐ray diffraction. The title compounds all crystallize in the monoclinic space group P21/c (no. 14) with lattice parameters: a = 7.9193(5), b = 9.4907(6), c = 8.8090(6) Å, β = 95.180(2)°, Z = 4 for RbFe(SO4)(C2O4)0.5 · H2O; a = 8.0654(11), b = 9.6103(13), c = 9.2189(13) Å, β = 94.564(4)°, Z = 4 for CsMn(SO4)(C2O4)0.5 · H2O; and a = 7.9377(3), b = 9.5757(4), c = 9.1474(4) Å, β = 96.1040(10)°, Z = 4 for CsFe(SO4)(C2O4)0.5 · H2O. All compounds exhibit three‐dimensional frameworks composed of [MO6] octahedra, [SO4]2– tetrahedra, and [C2O4]2– anions. The alkali cations are located in one‐dimensional tunnels.  相似文献   

2.
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   

3.
The title compound, [Fe(C10H15)2][Ni(C3OS4)2]·C4H8O or [Fe(Cp*)2][Ni(dmio)2]·THF, where [Fe(Cp*)2]+ is the deca­methyl­ferrocenium cation, dmio is the 2‐oxo‐1,3‐dithiole‐4,5‐dithiol­ate dianion and THF is tetra­hydro­furan, crystallizes with two independent half‐anion units [one Ni atom is at the centre of symmetry (, , 0) and the other is at the centre of symmetry (, 0, )], one cation unit (located in a general position) and one THF solvent mol­ecule in the asymmetric unit. The crystal structure consists of two‐dimensional layers composed of parallel mixed chains, where pairs of cations alternate with single anions. These layers are separated by sheets of anions and THF mol­ecules.  相似文献   

4.
Structure and Thermal Behaviour of Gadolinium(III)-sulfate-octahydrate Gd2(SO4)3 · 8 H2O . Gd2(SO4)3 · 8 H2O crystallizes monoclinic with space group C2/c and the lattice constants a = 13.531(7), b = 6.739(2), c = 18.294(7) Å, β = 102.20(8)°. In the structure Gd is coordinated by 4 oxygen atoms of crystal water and 4 oxygens of sulfate giving rise to a distorted square antiprism. During DTA-TG-experiments the title compound first loses crystal water in a two-step mechanism in the temperature range 130–306°C. The resulting Gd2(SO4)3 is amorphous and recrystallization occurs in the range 380–411°C. The so-obtained low-temperature modification β-Gd2(SO4)3, undergoes a monotropic phase transition at about 750°C to the high-temperature form α-Gd2(SO4)3. The powder pattern of this modification was indexed based on monoclinic symmetry with space group C2/c and lattice constants a = 9.097(3), b = 14.345(5), c = 6.234(2) Å, β = 97.75(8)°. The hightemperature modification of gadolinium-sulfate shows decomposition to Gd2O2SO4 at 900°C and, subsequently, decomposition at 1 200°C yields the formation of C-Gd2O3.  相似文献   

5.
The structure of synthetic disodium magnesium disulfate decahydrate at 180 K consists of alternating layers of water‐coordinated [Mg(H2O)6]2+ octahedra and [Na2(SO4)2(H2O)4]2− sheets, parallel to [100]. The [Mg(H2O)6]2+ octahedra are joined to one another by a single hydrogen bond, the other hydrogen bonds being involved in inter‐layer linkage. The Mg2+ cation occupies a crystallographic inversion centre. The sodium–sulfate sheets consist of chains of water‐sharing [Na(H2O)6]+ octahedra along b, which are then connected by sulfate tetrahedra through corner‐sharing. The associated hydrogen bonds are the result of water–sulfate interactions within the sheets themselves. This is believed to be the first structure of a mixed monovalent/divalent cation sulfate decahydrate salt.  相似文献   

6.
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   

7.
Synthesis and Characterization of Ca(HSO4)2 · 2 H2SO4 or H2[Ca(HSO4)4], respectively ?Ca(HSO4)2 · 2 H2SO4”? crystallizes from CaSO4 saturated hot H2SO4c below 310 K. With SOCl2 containing ether it is possible, to remove two moles H2SO4 and to prepare Ca(HSO4)2. ?Ca(HSO4)2 · 2 H2SO4”? shows two endothermal effects at Tp1 = 336 K and Tp2 = 477 K during the thermal analysis. Whereas Tp2 corresponds to the segregation of H2SO4 from Ca(HSO4)2, Tp1 is attributed to the loss of two moles H2SO4. These results are supported by x-ray heating measurements on single crystals. From oscillation and Weissenberg photographs with CuKα the unit cell was determined. In agreement with these parameters, the compound is to formulate as the complex acid H2[Ca(HSO4)4].  相似文献   

8.
H3OLa(SO4)2 · 3 H2O: A New Acidic Sulfate of the Rare Earth Elements Colorless single crystals of H3OLa(SO4)2 · 3 H2O have been obtained by the reaction of La2O3 and sulfuric acid (80% H2SO4) at 150 °C. In the crystal structure (monoclinic, P21/c, Z = 4, a = 1119.5(5), b = 693.3(2), c = 1357.4(4) pm, β = 110.94(4)°) La3+ is ninefold coordinated by oxygen atoms which belong to five SO4 ions and three H2O molecules. One of sulfate groups acts as a bidentate ligand. Hydrogen bonding is observed with H2O molecules as donors and acceptors. Furthermore, strong hydrogen bonds are formed between the H3O+ ions and oxygen atoms of the SO42– groups.  相似文献   

9.
Two new solid‐state uranium(IV) sulfate x‐hydrate complexes (where x is the total number of coordinated plus solvent waters), namely catena‐poly[[pentaaquauranium(IV)]‐di‐μ‐sulfato‐κ4O:O′] monohydrate], {[U(SO4)2(H2O)5]·H2O}n, and hexaaquabis(sulfato‐κ2O,O′)uranium(IV) dihydrate, [U(SO4)2(H2O)6]·2H2O, have been synthesized, structurally characterized by single‐crystal X‐ray diffraction and analyzed by vibrational (IR and Raman) spectroscopy. By comparing these structures with those of four other known uranium(IV) sulfate x‐hydrates, the effect of additional coordinated water molecules on their structures has been elucidated. As the number of coordinated water molecules increases, the sulfate bonds are displaced, thus changing the binding mode of the sulfate ligands to the uranium centre. As a result, uranium(IV) sulfate x‐hydrate changes from being fully crosslinked in three dimensions in the anhydrous compound, through sheet and chain linking in the tetra‐ and hexahydrates, to fully unlinked molecules in the octa‐ and nonahydrates. It can be concluded that coordinated waters play an important role in determining the structure and connectivity of UIV sulfate complexes.  相似文献   

10.
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   

11.
Preparation and Properties of Na2CuII (SO4)2 · 6 H2O The preparation of the complex compound of Na2Cu(SO4)2 · 6 H2O is described. Its structure and properties were investigated using spectral methods (u.v.-vis., i.r., n.m.r.), by means of X-ray powder diffraction, and by thermal methods. On the basis of experimental results it is suggested that another member of the Tutton salts series has been prepared, appearring isostructural with them and showing the less distorted coordination polyhedron of [Cu(H2O)6]2+ from them. On its dehydration oxygen atoms from the sulphate groups enter the coordination sphere of CuII and the symmetry of SO42? becomes lower. The experimental results indicate that Na2Cu(SO4)2 · 6 H2O as also Na2Cu(SO4)2 as likewise Na2Cu(SO4)2 · 2 H2O are monoclinic.  相似文献   

12.
A new chemical and structural interpretation of K5Ce2(SO4)6·H2O ( I ) and a redetermination of the structure of K2Ce(SO4)3·H2O ( II ) is presented. The mixed‐valent compound I crystallizes in the space group C2/c with a = 17.7321(3), b = 7.0599(1), c = 19.4628(4) Å, β = 112.373(1)° and Z = 4. Compound I has been discussed earlier with space group Cc. In the structure of I , there are pairs of edge sharing cerium polyhedra connected by sulfate oxygen atoms in the μ3 bonding mode. These cerium dimers are linked through edge and corner sharing sulfate bridges, forming layers. The layers are joined by potassium ions which together with the water molecules are placed between the layers. No irregularity in the distribution of the CeIII and CeIV to cause the lost of a crystallographic center of symmetry was detected. We suggest that the charge exerted by the extra f1 electron for every cerium dimer is delocalized over the Ce1–O2–Ce2 moiety in a non‐bonding mode. As a result, the oxidations state of each cerium ion is a mean value between III and IV at each atomic position. Compound II crystallizes in the space group C2 with a = 20.6149(2), b = 7.0742(1), c = 17.8570(1) Å, β = 122.720(1)° and Z = 8. The hydrogen atoms have been located and the absolute structure has been established. Neither hydrogen atom positions nor anisotropic displacement parameters were given in the previous reports. In compound II , the cerium polyhedra are connected by edge and corner sharing sulfate groups forming a three‐dimensional network. This network contains Z‐shaped channels hosting the charge compensating potassium ions.  相似文献   

13.
The structure of poly[[[hexaaquatrimanganese(II)]‐tri‐μ‐squarato] monohydrate], {[Mn3(C4O4)3(H2O)6]·H2O}n, synthesized hydrothermally, consists of a new three‐dimensional framework described by secondary building units (SBUs) containing two MnO6 octahedra and three squarate groups in a cube‐shaped arrangement. In the asymmetric unit, one squarate group is located around an inversion centre (4a; 0, 0, 0), two Mn atoms [4d (, , 0) and 4c (, , 0)] are located on inversion centres and the third Mn atom is on a twofold axis (4e; 0, y, ). This report illustrates the concept of the SBU and the flexibility of the squarate spacer in the design of new porous topologies.  相似文献   

14.
Syntheses, Crystal Structures, and Thermal Behavior of Er2(SO4)3 · 8 H2O and Er2(SO4)3 · 4 H2O Evaporation of aqueous solutions of Er2(SO4)3 yields light pink single crystals of Er2(SO4)3 · 8 H2O. X-ray single crystal investigations show that the compound crystallizes monoclinically (C2/c, Z = 8, a = 1346.1(3), b = 667.21(1), c = 1816.2(6) pm, β = 101.90(3)°, Rall = 0.0169) with eightfold coordination of Er3+, according to Er(SO4)4(H2O)4. DSC- and temperature dependent X-ray powder investigations show that the decomposition of the hydrate follows a two step mechanism, firstly yielding Er2(SO4)3 · 3 H2O and finally Er2(SO4)3. Attempts to synthesize Er2(SO4)3 · 3 H2O led to another hydrate, Er2(SO4)3 · 4 H2O. There are two crystallographically different Er3+ ions in the triclinic structure (P 1, Z = 2, a = 663.5(2), b = 905.5(2), c = 1046.5(2) pm, α = 93.59(3)°, β = 107.18(2)°, γ = 99.12(3)°, Rall = 0.0248). Er(1)3+ is coordinated by five SO42– groups and three H2O molecules, Er(2)3+ is surrounded by six SO42– groups and one H2O molecule. The thermal decomposition of the tetrahydrate yields Er2(SO4)3 in a one step process. In both cases the dehydration produces the anhydrous sulfate in a modification different from the one known so far.  相似文献   

15.
The title compound, di­ammonium aqua‐μ‐carbonato‐tri‐μ‐­oxalato‐dineodymium(III) hydrate, (NH4)2[Nd2(CO3)(C2O4)3(H2O)]·H2O, involving the two ligands oxalate and carbonate, has been prepared hydro­thermally as single crystals. The Nd atoms form a tetranuclear unit across the inversion centre at (,,). Starting from this tetranuclear unit, the oxalate ligands serve to develop a three‐dimensional network. The carbonate group acts as a bis‐chelating ligand to two Nd atoms, and is monodentate to a third Nd atom. The oxalate groups are all bis‐chelating. The two independent Nd atoms are ninefold coordinated and the coordination polyhedron of these atoms is a distorted monocapped antiprism.  相似文献   

16.
Hexaaquamagnesium(II) sulfate pentahydrate, [Mg(H2O)6]SO4·5H2O, and hexaaquamagnesium(II) chromate(II) pentahydrate, [Mg(H2O)6][CrO4]·5H2O, are isomorphous, being composed of hexaaquamagnesium(II) octahedra, [Mg(H2O)6]2+, and sulfate (chromate) tetrahedral oxyanions, SO42− (CrO42−), linked by hydrogen bonds. There are two symmetry‐inequivalent centrosymmetric octahedra: M1 at (0, 0, 0) donates hydrogen bonds directly to the tetrahedral oxyanion, T1, at (0.405, 0.320, 0.201), whereas the M2 octahedron at (0, 0, ) is linked to the oxyanion via five interstitial water molecules. Substitution of CrVI for SVI leads to a substantial expansion of T1, since the Cr—O bond is approximately 12% longer than the S—O bond. This expansion is propagated through the hydrogen‐bonded framework to produce a 3.3% increase in unit‐cell volume; the greatest part of this chemically induced strain is manifested along the b* direction. The hydrogen bonds in the chromate compound mitigate ∼20% of the expected strain due to the larger oxyanion, becoming shorter (i.e. stronger) and more linear than in the sulfate analogue. The bifurcated hydrogen bond donated by one of the interstitial water molecules is significantly more symmetrical in the chromate analogue.  相似文献   

17.
The title compound, tricaesium sodium iron(III) μ3‐oxido‐hexa‐μ2‐sulfato‐tris[aquairon(III)] pentahydrate, Cs2.91Na1.34Fe3+0.25[Fe3O(SO4)6(H2O)3]·5H2O, belongs to the family of Maus's salts, K5[Fe3O(SO4)6(H2O)3]·6H2O, which is based on the triaqua‐μ3‐oxido‐hexa‐μ‐sulfato‐triferrate(III) anion, [Fe3O(SO4)6(H2O)3]5−, with Fe in a characteristically distorted octahedral coordination environment, sharing a common corner via an oxide O atom. Cs in four different cation sites, Na in three different cation sites and five water molecules link the anions in three dimensions and set up a crystal structure in which those parts parallel to (001) and within 0.05 < z < 0.95 have a distinct trigonal pseudosymmetry, whereas the cation arrangement and bonding near z∼ 0 generate a clear‐cut noncentrosymmetric polar edifice with the monoclinic space group C2. The structure shows some cation disorder in the region near z ∼ , where one Na atom in octahedral coordination is partly substituted by Fe3+, and a Cs atom is substituted by small amounts of Na on a separate nearby site. One Na atom, located on a twofold axis at z = 0 and tetrahedrally coordinated by four sulfate O atoms of two [Fe3O(SO4)6(H2O)3]5− units, plays a key role in generating the noncentrosymmetric structure. Three of the seven different cation sites are on twofold axes (one Na+ site and two Cs+ sites), and all other atoms of the structure are in general positions.  相似文献   

18.
In the title compound, [Cu2(C15H11ClN2O3)2(C5H5N)2]·2CH3OH, the coordination geometry of the metal centre can be described as square pyramidal. Pairs of pentacoordinated metal centres are bridged by symmetry‐related phenolate O atoms about the inversion centre at (, 0, ), resulting in a binuclear metal cluster via edge‐sharing.  相似文献   

19.
Ferric sulfate trihydrate has been synthesized at 403 K under hydrothermal conditions. The structure consists of quadruple chains of [Fe2(SO4)3(H2O)3] parallel to [010]. Each quadruple chain is composed of equal proportions of FeO4(H2O)2 octahedra and FeO5(H2O) octahedra sharing corners with SO4 tetrahedra. The chains are joined to each other by hydrogen bonds. This compound is a new hydration state of Fe2(SO4)3·nH2O; minerals with n = 0, 5, 7.25–7.75, 9 and 11 are found in nature.  相似文献   

20.
IntroductionMolecularpolymerwithonedimensionalormultidimen sionalstructureassemblingthroughhydrogenbondsisanim portantresearchcontentinthesupramolecularchemistryandcrystalenginnering .1,2 Withthedevelopmentofnewtypefunctionalmaterialssuchasmolecularmagnetic ,selectedcatalysis ,reversiblecatalysis ,reversiblehost guestmolecular(ion)exchangeetc.,3themoleculardesignandsynthesishavealreadyattractedconsiderableattentioninsupramolecu larsystem .Thesupramolecularcomplexesandorganiccom poundscontainin…  相似文献   

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