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1.
The title compound, tricaesium sodium iron(III) μ 3‐oxido‐hexa‐μ 2‐sulfato‐tris[aquairon(III)] pentahydrate, Cs 2.91Na 1.34Fe 3+0.25[Fe 3O(SO 4) 6(H 2O) 3]·5H 2O, belongs to the family of Maus's salts, K 5[Fe 3O(SO 4) 6(H 2O) 3]·6H 2O, which is based on the triaqua‐μ 3‐oxido‐hexa‐μ‐sulfato‐triferrate(III) anion, [Fe 3O(SO 4) 6(H 2O) 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 Fe 3+, 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 [Fe 3O(SO 4) 6(H 2O) 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
2.
The glass formation region boundaries were found in the systems Al 2(SO 4) 3-MSO 4-H 2O, where M = Cd 2+, Zn 2+, and Mg 2+, and Al 2(SO 4) 3-Fe 2(SO 4) 3-H 2O. The causes of the differences in glass-forming ability between the studied systems were analyzed. The structures and properties of glassy Al 2(SO 4) 3 · 11H 2O and Fe 2(SO 4) 3 · 11H 2O were compared. 相似文献
3.
The title compound, diiron(III) trisulfate–sulfuric acid–water (1/1/28), has been prepared at temperatures between 235 and 239 K from acid solutions of Fe 2(SO 4) 3. Studies of the compound at 100 and 200 K are reported. The analysis reveals the structural features of an alum, (H 5O 2)Fe(SO 4) 2·12H 2O. The Fe(H 2O) 6 unit is located on a centre of inversion at (, 0, ), while the H 5O 2+ cation is located about an inversion centre at (, , ). The compound thus represents the first oxonium alum, although the unit cell is orthorhombic. 相似文献
4.
This study measures the osmotic coefficients of { xH 2SO 4 + (1− x)Fe 2(SO 4) 3}(aq) solutions at 298.15 and 323.15 K that have ionic strengths as great as 19.3 mol,kg −1, using the isopiestic method. Experiments utilized both aqueous NaCl and H 2SO 4 as reference solutions. Equilibrium values of the osmotic coefficient obtained using the two different reference solutions
were in satisfactory internal agreement. The solutions follow generally the Zdanovskii empirical linear relationship and yield
values of a
w for the Fe 2(SO 4) 3–H 2O binary system at 298.15 K that are in good agreement with recent work and are consistent with other M 2(SO 4) 3–H 2O binary systems. 相似文献
5.
The 57Fe Mössbauer spectra were measured in mixed crystals with different types of chemical bonding and crystal structure, i.e., (Fe,Al)(acac) 3, (Fe,Co)(acac) 3, K 3[(Fe,Al)(ox) 3]3H 2O, and NH 4(Fe,Al)(SO 4) 212H 2O. The broadening of Mössbauer linewidth with increasing Fe 3+–Fe 3+ distance became less enhanced in the order: (Fe,Al)(acac) 3>(Fe,Co)(acac) 3, or K 3[(Fe,Al)(ox) 3]3H 2O>(Fe,Al)(acac) 3>NH 4(Fe,Al)(SO 4) 212H 2O. Furthermore, it was found that the broadening of the linewidth was larger in neat tris (-diketonato) iron(III) complexes than in (Fe,Al)(acac) 3. Based on these results, the determining factors of the paramagnetic relaxation time other than Fe 3+–Fe 3+ distance and temperature were examined in terms of the Mössbauer linewidth as an indicator. 相似文献
6.
Fe 2O(SO 4) 2 is a secondary product of the decomposition of FeSO 4⋅H 2O. Part I of this study presents results on the synthesis of Fe 2O(SO 4) 2 in gaseous environment containing either low or high concentration of oxygen. In this paper the existence of differences
between the structures of Fe 2O(SO 4) 2 and Fe 2(SO 4) 3 is proved on the basis of a detailed thermal study of Fe 2O(SO 4) 2 upon dynamic heating (differential thermal analysis) and upon isothermal heating (thermal-analytic balance) in various gaseous
environments as well as by presenting kinetic data on the processes of decomposition of both compounds.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Acidic Sulfates of Neodymium: Synthesis and Crystal Structure of (H 5O 2)(H 3O) 2Nd(SO 4) 3 and (H 3O) 2Nd(HSO 4) 3SO 4 Light violett single crystals of (H 5O 2)(H 3O) 2 · Nd(SO 4) 3 are obtained by cooling of a solution prepared by dissolving neodymium oxalate in sulfuric acid (80%). According to X‐ray single crystal investigations there are H 3O + ions and H 5O 2+ ions present in the monoclinic structure (P2 1/n, Z = 4, a = 1159.9(4), b = 710.9(3), c = 1594.7(6) pm, β = 96.75(4)°, R all = 0.0260). Nd 3+ is nine‐coordinate by oxygen atoms. The same coordination number is found for Nd 3+ in the crystal structure of (H 3O) 2Nd(HSO 4) 3SO 4 (triclinic, P1, Z = 2, a = 910.0(1), b = 940.3(1), c = 952.6(1) pm, α = 100.14(1)°, β = 112.35(1)°, γ = 105.01(1)°, R all = 0.0283). The compound has been prepared by the reaction of Nd 2O 3 with chlorosulfonic acid in the presence of air. In the crystal structure both sulfate and hydrogensulfate groups occur. In both compounds pronounced hydrogen bonding is observed. 相似文献
8.
Ferric sulfate trihydrate has been synthesized at 403 K under hydrothermal conditions. The structure consists of quadruple chains of [Fe 2(SO 4) 3(H 2O) 3] parallel to [010]. Each quadruple chain is composed of equal proportions of FeO 4(H 2O) 2 octahedra and FeO 5(H 2O) octahedra sharing corners with SO 4 tetrahedra. The chains are joined to each other by hydrogen bonds. This compound is a new hydration state of Fe 2(SO 4) 3· nH 2O; minerals with n = 0, 5, 7.25–7.75, 9 and 11 are found in nature. 相似文献
9.
The crystal structure of oxonium neodymium bis(sulfate), (H 3O)Nd(SO 4) 2, shows a two‐dimensional layered framework assembled from SO 4 tetrahedra and NdO 9 tricapped trigonal prisms. One independent sulfate group makes four S—O—Nd linkages, while the other makes five such connections to generate an unprecedented anhydrous anionic [Nd(SO 4) 2] − layer. To achieve charge balance, H 3O + cations are inserted between adjacent layers where they participate in hydrogen‐bonding interactions with the sulfate O atoms of adjacent layers. 相似文献
10.
The crystal structures of 1,4-diazabicyclo[2.2.2]octane (dabco)-templated iron sulfate, (C 6H 14N 2)[Fe(H 2O) 6](SO 4) 2, were determined at room temperature and at −173 °C from single-crystal X-ray diffraction. At 20 °C, it crystallises in the monoclinic symmetry, centrosymmetric space group P2 1/ n, Z=2, a=7.964(5), b=9.100(5), c=12.065(5) Å, β=95.426(5)° and V=870.5(8) Å 3. The structure consists of [Fe(H 2O) 6] 2+ and disordered (C 6H 14N 2) 2+ cations and (SO 4) 2− anions connected together by an extensive three-dimensional H-bond network. The title compound undergoes a reversible phase transition of the first-order at −2.3 °C, characterized by DSC, dielectric measurement and optical observations, that suggests a relaxor–ferroelectric behavior. Below the transition temperature, the compound crystallizes in the monoclinic system, non-centrosymmetric space group Cc, with eight times the volume of the ambient phase: a=15.883(3), b=36.409(7), c=13.747(3) Å, β=120.2304(8)°, Z=16 and V=6868.7(2) Å 3. The organic moiety is then fully ordered within a supramolecular structure. Thermodiffractometry and thermogravimetric analyses indicate that its decomposition proceeds through three stages giving rise to the iron oxide. 相似文献
11.
Reaction of either K 3[Fe(CN) 6] or K 4[Fe(CN) 6] with a macrocyclic Cu II complex, [Cu(teta)](ClO 4) 2 (teta = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacylotetradecane), in aqueous solution gave the same product as shown by spectroscopic and physicochemical characterisation. The crystal structure of the complex shows that it is a one-dimensional linear chain type heterobinuclear Fe III–Cu II polymer. The unit is composed of a [Cu(teta)(H 2O) 2] 2+ cationic complex, a Fe III–Cu II alternate linear chain unit, a ClO
4
–
ion and four water molecules. The Cu atom is coordinated in a distorted octahedral arrangement by four nitrogen atoms from one teta ligand and two nitrogen atoms of the bridging cyanide groups. The Cu—N bond distances involving the cyanide bridges, 2.522(7) and 2.608(7)Å, respectively, indicate weak antiferromagnetic interactions between the Fe III and Cu II atoms. 相似文献
12.
The structure of two trinuclear iron acetates [Fe 3O(CH 3COO) 6(H 2O) 3]Cl· 6H 2O (I) and [Fe 3O(CH 3COO) 6(H 2O) 3][FeCl 4] · 2CH 3COOH (II) was determined by X-ray diffraction analysis. Crystals I and II are ionic and belong to the orthorhombic system with parameters a = 13.704(3), b = 23.332(5), c = 9.167(2) Å, R = 0.0355, space goup P2 12 12 for I and a = 10.145(4), b = 15.323(6), c = 22.999(8) Å, R = 0.0752, space group Pbc2 1 for II. The complex cation [Fe 3O(CH 3COO) 6(H 2O) 3] + has a μ 3-O-bridged structure typical for trinuclear iron (III) compounds. As shown by Mössbauer spectroscopy, the iron(III) ions are in the high-spin state. In trinuclear cations, antiferromagnetic exchange interaction takes place between the Fe(III) ions with the exchange parameter J = -26.69 cm ?1 for II (Heisenberg-Dirac-Van Vleck model for D 3h, symmetry). 相似文献
13.
The data on the thermal decomposition of FeSO4?H2O upon various regimes of heating and gaseous environment prove the formation of intermediate products of the types Fe2O(SO4)2 and FeOHSO4, their stability and amount being determined mainly by temperature and oxygen-reduction potential. This communication aims at presenting results on the synthesis and characterization of Fe2O(SO4)2. The synthesis was carried out using a laboratory thermal equipment operating under isothermal conditions in the temperature range 713–813 K in a gaseous environment either poor in oxygen or containing 100% oxygen. The experimental conditions under which Fe2O(SO4)2 is stable are established. The effect of three basic parameters on the synthesis of Fe2O(SO4)2 is clarified: the oxygen partial pressure, the ratio PH2O/PO2 and the temperature and the mode of heating. Mössbauer spectroscopy and X-ray diffraction data for Fe2O(SO4)2 are presented. 相似文献
14.
In order to efficiently remove phosphorus, thermodynamic equilibrium diagrams of the P-H 2O system and P-M-H 2O system (M stands for Fe, Al, Ca, Mg) were analyzed by software from Visual MINTEQ to identify the existence of phosphorus ions and metal ions as pH ranged from 1 to 14. The results showed that the phosphorus ions existed in the form of H 3PO 4, H 2PO 4−, HPO 42−, and PO 43−. Among them, H 2PO 4− and HPO 42− were the main species in the acidic medium (99% at pH = 5) and alkaline medium (97.9% at pH = 10). In the P-Fe-H 2O system ((P) = 0.01 mol/L, (Fe 3+) = 0.01 mol/L), H 2PO 4− was transformed to FeHPO 4+ at pH = 0–7 due to the existence of Fe 3+ and then transformed to HPO 42− at pH > 6 as the Fe 3+ was mostly precipitated. In the P-Ca-H 2O system ((P) = 0.01 mol/L, (Ca 2+) = 0.015 mol/L), the main species in the acidic medium was CaH 2PO 4+ and HPO 42−, and then transformed to CaPO 4− at pH > 7. In the P-Mg-H 2O system ((P) = 0.01 mol/L, (Mg 2+) = 0.015 mol/L), the main species in the acidic medium was H 2PO 4− and then transformed to MgHPO 4 at pH = 5–10, and finally transformed to MgPO 4− as pH increased. The verification experiments (precipitation experiments) with single metal ions confirmed that the theoretical analysis could be used to guide the actual experiments. 相似文献
15.
Syntheses, Crystal Structures, and Thermal Behavior of Er 2(SO 4) 3 · 8 H 2O and Er 2(SO 4) 3 · 4 H 2O Evaporation of aqueous solutions of Er 2(SO 4) 3 yields light pink single crystals of Er 2(SO 4) 3 · 8 H 2O. 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)°, R all = 0.0169) with eightfold coordination of Er 3+, according to Er(SO 4) 4(H 2O) 4. DSC- and temperature dependent X-ray powder investigations show that the decomposition of the hydrate follows a two step mechanism, firstly yielding Er 2(SO 4) 3 · 3 H 2O and finally Er 2(SO 4) 3. Attempts to synthesize Er 2(SO 4) 3 · 3 H 2O led to another hydrate, Er 2(SO 4) 3 · 4 H 2O. There are two crystallographically different Er 3+ 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)°, R all = 0.0248). Er(1) 3+ is coordinated by five SO 42– groups and three H 2O molecules, Er(2) 3+ is surrounded by six SO 42– groups and one H 2O molecule. The thermal decomposition of the tetrahydrate yields Er 2(SO 4) 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
16.
The crystal structure of a trinuclear iron monoiodoacetate complex was determined. Although it has been incorrectly characterized as [Fe 3O(O 2CCH 2I) 6(H 2O) 3], the correct chemical formula turned out to be [Fe(III) 2Fe(II)O(O 2CCH 2I) 6(H 2O) 3]-[Fe(III) 3O(O 2CCH 2I) 6(H 2O) 3]I ( 1). The two kinds of Fe 3O molecules (Fe(III) 2Fe(II)O and Fe(III) 3O) are crystallographically indistinguishable. All the Fe atoms are crystallographically equivalent because of a crystallographic threefold symmetry. Heat capacities of 1 seem to exhibit no thermal anomaly in the temperature range 5.5–309 K, although the valence detrapping phenomenon has been observed in this temperature range. This fact indicates that the valence-detrapping phenomenon in 1 occurs without any phase transition, leading 1 to a glassy state, probably because the crystal of 1 is just like a solid solution of distorted mixed-valence Fe(III) 2Fe(II)O molecules and permanently undistorted Fe(III) 3O molecules which may act as an inhibitor for a cooperative valence-trapping. 相似文献
17.
The crystal structure of ditellurium(IV)-trioxide sulfate, Te 2O 3(SO 4)—space group Pmn2 1–C
2v
7
; a=8.879 (2), b=6.936 (2), c=4.646 (4) Å, Z=2—has been determined and refined by least-squares, using three-dimensional X-ray data (1188 independent reflexions) to a final R-value of 6.3%.The crystal structure comprises puckered tellurium(IV)—oxygen layers in which the tellurium atoms are linked together by three oxygen bridges (Te–O 1.907, 1.945, 2.011 Å). The SO 4 groups are arranged between these layers. Two oxygen atoms of each SO 4 group are bonded to two adjacent tellurium atoms of one layer [Te–O(S) 2.270 Å] and the tellurium atoms show a (3+1) coordination. A third oxygen atom of the SO 4 group is in weak interaction with two adjacent tellurium atoms of the same layer (Te–O 2.603 Å) whereas the fourth oxygen atom has distances of 2.866 Å to two adjacent tellurium atoms of the next layer and effects a very weak interaction between the
Mit 3 Abbildungen
Herrn Prof. Dr. R. Kieffer zu seinem 70. Geburtstag gewidmet. 相似文献
18.
A new polymorph of Bi 2(SO 4) 3 was prepared by reaction of LiBiO 2 with H 2SO 4 and its crystal structure was solved from X-ray powder diffraction. This new polymorph crystallizes in C2/ c space group with lattice parameters a = 17.3383(3) Å, b = 6.77803(12) Å, c = 8.30978(13) Å, β = 101.4300(12)°. Bi 2(SO 4) 3 presents a layered structure made of SO 4 sulfate groups and signs of stereochemically active Bi 3+ lone pairs. The new Bi 2(SO 4) 3 absorbs water to form Bi 2(H 2O) 2(SO 4) 2(OH) 2 through an intermediate Bi 2O(OH) 2SO 4 phase, and the transition is reversible when heated under vacuum. 相似文献
19.
Coincidence Mössbauer spectra of 57Co-labelled [CoFe 2O(CH 3CO 2) 6(H 2O) 3] were determined at 78 K and 298 K with three timewindows of 0–50, 50–150 and 150–300 ns. Temperature dependence in the spectral shape ascribed to an intramolecular electron transfer was observed in all the time-window spectra, while little time dependence was observed. The results indicate that 57Fe atoms produced by EC-decay are incorporated in a chemical environment similar to that of the parent 57Co atoms, forming a trinuclear Fe IIFe 2
III structure at an early stage after the EC-decay.after April 1, 1991. 相似文献
20.
[Cu 2(μO 2CCH 3) 4(H 2O) 2], [CuCO 3·Cu(OH) 2], [CoSO 4·7H 2O], [Co((+)-tartrate)], and [FeSO 4·7H 2O] react with excess racemic (±)- 1,1′-binaphthyl-2,2′-diyl hydrogen phosphate {(±)-PhosH} to give mononuclear Cu II, Co II and Fe II products. The cobalt product, [Co(CH 3OH) 4(H 2O) 2]((+)-Phos)((−)-Phos) ·2CH 3OH·H 2O (7), has been identified by X-ray diffraction. The high-spin, octahedral Co II atom is ligated by four equatorial methanol molecules and two axial water molecules. A (+)- and a (−)-Phos − ion are associated with each molecule of the complex but are not coordinated to the metal centre. For the other Co II, Cu II and Fe II samples of similar formulation to ( 7) it is also thought that the Phos − ions are not bonded directly to the metal. When some of the Cu II and Co II samples are heated under high vacuum there is evidence that the Phos − ions are coordinated directly to the metals in the products. 相似文献
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