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1.
Potassium cobalt hydrogenpyrophosphate dihydrate, KHCoP2O7·2H2O, crystallizes in the orthorhombic space group Pnma. This salt is isotypic with KHMP2O7·2H2O (M = Mn and Zn). The structure consists of alternating layers, built from HP2O73− acidic pyrophosphate groups and CoO6 octahedra, joined by potassium ions and bridging hydrogen bonds. The Co, K and water O atoms lie on mirror planes. The pyrophosphate group consists of two symmetry‐related PO4 groups, with the bridging O atom on a mirror plane.  相似文献   

2.
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   

3.
Single crystals of calcium bromide enneahydrate, CaBr2·9H2O, calcium iodide octahydrate, CaI2·8H2O, calcium iodide heptahydrate, CaI2·7H2O, and calcium iodide 6.5‐hydrate, CaI2·6.5H2O, were grown from their aqueous solutions at and below room temperature according to the solid–liquid phase diagram. The crystal structure of CaI2·6.5H2O was redetermined. All four structures are built up from distorted Ca(H2O)8 antiprisms. The antiprisms of the iodide hydrate structures are connected either via trigonal‐plane‐sharing or edge‐sharing, forming dimeric units. The antiprisms in calcium bromide enneahydrate are monomeric.  相似文献   

4.
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   

5.
Chemical, Thermoanalytical, and X-ray Investigations to the Formation of the β-Ca2[P2O7] from the Ca2[P4O12] · 4 H2O The formation of β-Ca2[P2O7] from Ca2[P4O12] · 4 H2O (modification I) proceeds crystallographically oriented in several steps: In one of these steps an X-ray amorphous phase is formed and simultaneously cyclotetraphosphate reorganizes to polyphosphate. The dehydration proceeds in 2 steps: At 120°C 3 molecules and at 220°C 1 molecule are lost, respectively. The formation of diphosphate from polyphosphate, which is connected with the loss of P2O5, takes place at 850°C according to high temperature Guinier.  相似文献   

6.
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   

7.
(Solid+Liquid) phase equilibria in the quaternary system Na2B4O7‐MgB4O7‐K2B4O7‐H2O at 288 K were studied experimentally using the method of isothermal solution saturation. Solubility of any single salt in the solution of the quaternary system was determined experimentally. Based on the experimental data achieved, the phase diagram and water content diagram of the quaternary system were constructed, respectively. In the phase equilibrium diagram of the quaternary system Na2B4O7‐MgB4O7‐K2B4O7‐H2O at 288 K, there are one invariant point E, three univariant curves E1E, E2E and E3E, and three fields of crystallization corresponding to Na2B4O7·10H2O, K2B4O7·4H2O and MgB4O7·9H2O. The experimental results show that potassium borate (K2B4O7·4H2O) have higher solubilities than the magnesium borate and sodium borate in the quaternary system Na2B4O7‐MgB4O7‐K2B4O7‐H2O at 288 K.  相似文献   

8.
Hydrogen peroxosolvated compounds containing up to 16% H2O2 have been synthesized by reacting the calcium cyclopolyphosphates NaCaP3O9 · 2H2O, Ca2P4O12 · 4H2O, and Ca3P6O18 · 9H2O with hydrogen peroxide vapor or with a 70–96% hydrogen peroxide solution. In these reactions, hydrogen peroxide serves both as a source of solvating H2O2 and a dehydrating agent. Nanosized peroxosolvated calcium polyphosphates have been obtained using an organic template (gelatin). The compounds have been characterized by scanning electron microscopy, IR spectroscopy, X-ray diffraction, and thermal analysis.  相似文献   

9.
Single crystals of Rb2H2P2O6 · 2H2O could be obtained from aqueous solutions of hypodiphosphoric acid and rubidium carbonate. Its crystal structure was determined by X‐ray diffraction and it crystallizes in the monoclinic space group P21/c with Z = 4. The salt‐like title compound consists of [H2P2O6]2– units in staggered P2O6‐skeleton conformation, Rb+ cations, and H2O molecules, held together by intermolecular hydrogen bonds of the type O ··· O. The vibrational spectra (IR/FIR and Raman) of the rubidium salt were recorded and an assignment of the vibrational modes is proposed based on the point group C2h for the P2O6‐skeleton of the anion. The thermal behavior of Rb2H2P2O6 · 2H2O is dominated by a complex TG decay indicating a simultaneous H2O delivery coupled with a disproportionation of [H2P2O6]2–, what is also supported by Raman spectra of heated samples.  相似文献   

10.
IntroductionThesynthesisandsorptionpropertiesofopenframe worksolidssuchaszeolites1andmetalmolybdenumphos phate2 ,3withlargecavitiesprovokedenormousinterestbe causeoftheirpotentialapplicationincatalysis .One ,two andthree dimensionalsolidcompoundsconsistingo…  相似文献   

11.
High-temperature differential scanning calorimetry was used to investigate the thermodynamic parameters of the γ–β and β–α transitions in calcium pyrophosphate (Ca2P2O7). The measured enthalpy of transition compared well with previous results when higher heating rates (≥20 K min?1) were used. Recommendations for optimal use of HTDSC in high-temperature phase transition measurements are presented.  相似文献   

12.
Concentrated aqueous solutions of magnesium chloride and calcium nitrate, respectively, allow on addition of the potassium salt of tetrathiosquarate, K2C4S4 · H2O, the isolation of the earth alkaline salts MgC4S4 · 6 H2O ( 1 ) and CaC4S4 · 4 H2O ( 2 ) as orange and red crystals. The crystal structure determinations ( 1 : monoclinic, C2/c, a = 17.2280(7), b = 5.9185(2), c = 13.1480(4) Å, β = 104.730(3)°, Z = 4; 2 : monoclinic, P21/m, a = 7.8515(3), b = 12.7705(5), c = 10.6010(4) Å, β = 93.228(2)°, Z = 4) show the presence of C4S42? ions with almost undistorted D4h symmetry having average C–C and C–S bond lengths of 1.451Å and 1.659Å for 1 and 1.451Å and 1.655Å for 2 . The structure of 1 contains discrete, octahedral [Mg(H2O)6]2+ complexes. Several O–H····O and O–H····S bridges with H····O and H····S distances of less than 2.50Å connect cations and anions. The structure of 2 is built of concatenated, edge‐sharing Ca(H2O)6S2 polyhedra. The Ca2+ ions have the coordination number eight, C4S42? act as a chelating ligands towards Ca2+ with Ca–S distances of 3.14Å. The infrared and Raman spectra show bands typical for the molecular building units of the two compounds.  相似文献   

13.
Crystallographic Orientation Relations between the Phases in the Reaction Ca2[P4O12] · 4 H2O → β-(Ca2[PO3]4)x The dehydration of Ca2[P4O12] · 4 H2O modification I proceeds over several intermediate phases to β-(Ca2[PO3]4)x crystallographically oriented. One of the intermediate phases is X-ray amorphous. It is of special interest, that this amorphous phase does not interrupt the oriented course of the reaction. The β-polyphosphate transforms to β-Ca2[P2O7] connected with the loss of P2O5 at further heating. The crystallographic orientation relations between educt and product were determined for all steps of the reaction. The unit cells of the phases were determined too.  相似文献   

14.
Several rare‐earth cyclotriphosphate hydrates were obtained from mixtures of sodium cyclotriphosphates and the respective rare‐earth chlorides. Nd(P3O9) · 3H2O [P$\bar{6}$ , Z = 3, a = 677.90(9), c = 608.67(9) pm, R1 = 0.016, wR2 = 0.038, 312 data, 36 parameters] was obtained by a solid state reaction and is isotypic with respective rare‐earth phosphate hydrates, while all the others adopt new structure types. Nd(P3O9) · 4.5H2O [C2/c, Z = 8, a = 1644.6(3), b = 756.11(15), c = 1856.1(4) pm, β = 97.25(3)°, R1 = 0.032, wR2 = 0.081, 1763 data, 194 parameters], Nd(P3O9) · 5H2O [P21/c, Z = 4, a = 773.75(15), b = 1149.1(2), c = 1394.9(3) pm, β = 106.07(3)°, R1 = 0.042, wR2 = 0.082, 1338 data, 194 parameters], Pr(P3O9) · 5H2O [P$\bar{1}$ , Z = 2, a = 745.64(15), b = 889.07(18), c = 934.55(19) pm, α = 79.00(3), β = 80.25(3), γ = 66.48(3), R1 = 0.059, wR2 = 0.089, 1468 data, 193 parameters], Na3Nd(P3O9)2 · 6H2O [P21/n, Z = 4, a = 1059.78(18), b = 1207.25(15), c = 1645.7(4) pm, β = 99.742(17), R1 = 0.047, wR2 = 0.119, 1109 data, 351 parameters] and Na3Pr(P3O9)2 · 6H2O [P21/n, Z = 4, a = 1061.42(16), b = 1209.0(2), c = 1635.5(3) pm, β = 99.841(13), R1 = 0.035, wR2 = 0.062, 1323 data, 350 parameters] were obtained by careful crystallization at room temperature. A thorough structure discussion is given. The infrared spectrum of Nd(P3O9) · 4.5H2O is also reported.  相似文献   

15.
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   

16.
The new thallium(I) salts, Tl2H2P2O6 ( 1 ) and Tl4P2O6 ( 2 ), were prepared and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 crystallizes in the monoclinic space group P21/c and compound 2 in the orthorhombic space group Pbca. Both structures feature channels occupied by the lone electron pairs of Tl+ cations. Furthermore, those are built up by discrete [H2P2O6]2– for compound 1 and [P2O6]4– units for 2 in staggered conformation for the P2O6 skeleton and the thallium cations. In Tl2H2P2O6 ( 1 ) the hydrogen atoms of the [H2P2O6]2– ion are in a “trans‐trans” conformation. The O ··· H–O hydrogen bonds between the [H2P2O6]2– groups consolidate the structure 1 into a three‐dimensional network. FT‐IR/FIR and FT‐Raman spectra of the crystalline title compounds were recorded and a complete assignment for the P2O64– modes is proposed. The phase purity of 1 was verified by powder diffraction measurements.  相似文献   

17.
Synthesis and Crystal Structure of Cs8P8O24 · 8H2O Cs8P8O24 · 8H2O was obtained from Na8P8O24 · 6H2O by cation exchange. Crystal growth was achieved by applying gel techniques (agar agar). The crystal structure (P1 ; a = 766.6(8); b = 1 156.9(9); c = 1 163.4(9) pm; α = 100,2(1)°; β = 106.5(2)°; γ = 92.2(1)°; Z = 1; 4 099 unique diffractometer data; R = 0.051; R(w) = 0.037) contains cyclo-octaphosphate anions with point symmetry C2h. The cesium atoms are coordinated irregularily by eight and ten oxygen atoms, respectively. The threedimensional linkage of the P8O248?-rings is established via bonds to cesium atoms and hydrogen bonds Provided by H2O molecules.  相似文献   

18.
Crystal Structure of Na5P3O10 · 6 H2O Na5P3O10 · 6 H2O crystallizes triclinic in P1 with a = 1 037.0(2), b = 984.8(4), c = 761.5(3) pm; α = 92.24(7)°, β = 94.55(9), γ = 90.87(6)°; Z = 2. The structure has been determined from fourcycle diffractometer data (2 089 independent reflections, R = 0.053). All hydrogen positions have been taken from a weighted difference-fourier-syntheses. Na5P3O10 · 6 H2O forms colorless, plate-like crystals, which are twinned systematically parallel (001) and can be divided mechanically into single-crystalline portions.  相似文献   

19.
The binuclear praseodymium(III) complex with N‐(1‐carboxyethylidene)‐salicylhydrazide (C10H10N2O4, H2L) was prepared in H2O‐C2H5OH mixed solution, and the crystal structure of [Pr2L2(HL)2(H2O)4]·3H2O·C6H6 was determined by X‐ray single crystal diffraction. The crystal complex crystallizes in the triclinic system with space group P‐1, and in the structure each Pr atom is 9‐coordinated by carboxyl O and acyl O and azomethine N atoms of two tridentate ligands to form two stable five‐membered rings sharing one side in keto‐mode and two water molecules. The coordination polyhedron around Pr3+ was described as a monocapped square antiprism geometry. In an individual molecule, four tridentate ligands were coordinated by two negative univalent (HL) and two bivalent forms (L) respectively. Two negative univalent ligands were coordinated via μ2‐bridging mode.  相似文献   

20.
The crystal structures of three isotypic ortho­rhom­bic dihydrogendiphosphates, namely dipotassium copper(II)/nickel(II)/zinc(II) bis­(dihydrogendiphosphate) dihydrate, K2M(H2P2O7)2·2H2O (M = Cu, Ni and Zn), have been refined from single‐crystal data. The M2+ and K+ cations are located at sites of m symmetry, and the P atoms occupy general positions. These compounds also exist in triclinic forms with very similar structural features. The structures of both forms are compared, as well as the geometry of the MO6 octa­hedron, which is considerably elongated towards the water mol­ecules for M = Ni and Cu. Such elongation has not been observed among the other representatives of the family. A Raman study of the whole series K2M(H2P2O7)2·2H2O (M = Mn, Co, Ni, Cu, Zn and Mg) is reported.  相似文献   

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