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1.
Oligomeric Diacetyl Phosphates Sodium, potassium, and ammonium salts of the dipho sphoric and triphosphoric acid react at room temperatur to symmetrical diacetyl diphosphates and diacetyl triphosphates respectively, which was demonstrated unequivocally by 31P-NMR spectroscopy. The preparation of potassium and ammonium diacetyldiphosphate is described. Ammonium triphosphate reacts with acetic anhydride yielding a new modification of the ammonium cyclotriphosphate, (NH4)3P3O9II.  相似文献   

2.
A study of the vibrational spectra and physico-chemical properties of nickel and sodium cyclotriphosphate hexahydrate, NiNa4(P3O9)2.6H2O. We have studied the dehydration and the calcination under atmospheric pressure of cyclotriphosphate hexahydrate of nickel and sodium, NiNa4(P3O9)2.6H2O, between 25 and 700°C by infrared spectrometry, X-ray diffraction, TGA and DTA thermal analyses. This study allows the identification and the crystallographic characterization of a new phase, NiNa4(PO3)6, obtained between 350 and 450°C. NiNa4(PO3)6 crystallizes in the triclinic system, P−1, with the following unit cell parameters a = 6.157(3)Å, b = 6.820(6)Å, c = 10.918(6)Å, α = 80.21(5)°, β= 97.80(9)°, γ = 113.49(3)°, V = 409.8 Å3, Z = 1, M(19) = 25 and F(19) = 48 (0.0095; 42). The calcination of NiNa4(PO3)6, between 500 and 600°C, leads to a mixture of long-chain polyphosphates NiNa(PO3)3 and NaPO3. The kinetic characteristics of the dehydration of NiNa4(P3O9)2.6H2O were determined and discussed. The vibrational spectrum of the title compound, NiNa4(P3O9)2.6H2O, was interpreted in the domain of the stretching vibrations of the P3O9 rings, on the basis of its crystalline structure and in the light of the calculation of the normal IR frequencies of the P3O9 ring with D3h symmetry.  相似文献   

3.
Abstract

Chemical presparation, thermal behavior, and infrared (IR) studies are discussed for the cyclotriphosphate MnK4(P3O9)2.2H2O and its anhydrous form MnK4(P3O9)2. The total dehydration of MnK4(P3O9)2.2H2O, between 200 and 550 °C, leads to its anhydrous form MnK4(P3O9)2. MnK4(P3O9)2 is a new cyclotriphosphate crystallizing in the rhombohedral system and is stable until its melting point at 560 °C. The thermal behavior of MnK4(P3O9)2.2H2O has been investigated and interpreted by comparison with IR absorption spectrometry and X-ray diffraction experiments. Two different methods, Ozawa and KAS (Kissinger-Akahira-Sunose), were selected in studying the kinetics of thermal behavior of the title compound. Quantum chemical calculations were made for the P3O 3? 9 ion.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

GRAPHICAL ABSTRACT  相似文献   

4.
The design of structurally well‐defined anionic molecular metal–oxygen clusters, polyoxometalates (POMs), leads to inorganic receptors with unique and tunable properties. Herein, an α‐Dawson‐type silicotungstate, TBA8[α‐Si2W18O62] ? 3 H2O ( II ) that possesses a ?8 charge was successfully synthesized by dimerization of a trivacant lacunary α‐Keggin‐type silicotungstate TBA4H6[α‐SiW9O34] ? 2 H2O ( I ) in an organic solvent. POM II could be reversibly protonated (in the presence of acid) and deprotonated (in the presence of base) inside the aperture by means of intramolecular hydrogen bonds with retention of the POM structure. In contrast, the aperture of phosphorus‐centered POM TBA6[α‐P2W18O62]?H2O ( III ) was not protonated inside the aperture. The density functional theory (DFT) calculations revealed that the basicities and charges of internal μ3‐oxygen atoms were increased by changing the central heteroatoms from P5+ to Si4+, thereby supporting the protonation of II . Additionally, II showed much higher catalytic performance for the Knoevenagel condensation of ethyl cyanoacetate with benzaldehyde than I and III .  相似文献   

5.
The stoichiometry of the interaction of Ca2+ with sodium triphosphate was determined using a Ca2+ sensitive electrode, divalent ion sensitive electrode, a glass electrode and by titration calorimetry, A 2:1 and 1:1 complex of Ca2+ and P3O5?10 is found when titrating calcium chloride with sodium triphosphate by the calcium ion sensitive electrode and tritation calorimetry. However, only by titration calorimetry is the 2:1 and 1:1 complex found when titrating sodium triphosphate with calcium chloride. Thermodynamic value (log K, ΔH and ΔS) are reported for the formation of CaP(in3)O?310 and Ca2P3O?10 in aqueous solution.  相似文献   

6.
In the preparation of Ba2H2(H2P2O4)3 by P2I4 hydrolysis in barium acetate/acetic acid buffer solution P(II)—P(IV), P(IV)—P(IV), P(III), and P(V) acid are formed in addition to about 17% of the starting phosphorus as P(II)—P(II) acid after separating the Ba2H2(H2P2O4)3. Thus in this reaction a total of 64% of P2I4 Phosphorus can be detected as hypodiphosphorous acid H4P2O4. The precipitated yellow reaction product, obtained by water hydrolysis of P2I4, contains no solid phosphorus hydride — as believed previously — but as a result of elementary analysis, iodometry, and chromatography, a high molecular-weight phosphorus, hydrogen and oxygen containing substance of statistical stoichiometry with oxydation number ~0 for phosphorus. P? H, P?O, and P? O? P groups could be detected by IR-spectroscopy, but not P? OH groups. The P2I4 hydrolysis probably proceeds via a yellow coloured initial product with trivalent phosphorus, and yields a very complex reaction mixture in which also the intermediates partially still react further.  相似文献   

7.
By electrolysis of cryolitic solutions of P2O5, elementary pure phosphorus is obtained on carbon cathode and Ni phosphides on Ni cathode. The most probable mechanism of phosphorus formation in these conditions seems to be the final dissociation of P2O5 in P5+ and O2? and the primary electrodic discharge of these ions.  相似文献   

8.
The title compounds, C20H25N2O2S+·I?, (I), and C29H25BrN2O2S, (II), respectively, both crystallize in space group P. The pyrrole ring subtends an angle with the sulfonyl group of 33.6° in (I) and 21.5° in (II). The phenyl ring of the sulfonyl substituent makes a dihedral angle with the best plane of the indole moiety of 81.6° in (I) and 67.2° in (II). The lengthening or shortening of the C—N bond distances in both compounds is due to the electron‐withdrawing character of the phenyl­sulfonyl group. The S atoms are in distorted tetrahedral configurations. The molecular structures are stabilized by C—H?O and C—H?I interactions in (I), and by C—H?O and C—H?N interactions in (II).  相似文献   

9.
A new layered phosphate, Na7Y2(P2O7) 2(P3O10), containing both [P2O7]4? and [P3O10]5? groups, has been prepared. It crystallizes in the monoclinic space group P2/c with a = 16.205(4), b = 5.3746(9), c = 12.309(4) Å, β = 97.96(2)°, V = 1061.7(5) Å3 and Z = 2. The structure was solved and refined to R1 = 0.0298 and wR2 = 0.0698 for 1844 independent reflections with I > 2σ(I). It consists of layers of corner and edge-sharing YO7 polyhedra, P2O7 and P3O10 groups. Each layer is built up from two parallel [YP2O7] slabs, held together by the P3O10 groups. This arrangement gives rise to intersecting tunnels within the layer. The Na+ cations are located in the tunnels and between the layers. Both P2O7 and P3O10 groups contain unshared oxygen atoms directed toward the interlayer space and toward the tunnels. The P2O7 groups show a staggered configuration. In addition to this original layered framework, the title compound provides the third example of a compound containing a mixed anion of [P2O7]4? and [P3O10]5?. The structure was compared with the two previously reported ones, containing such a mixed anion: NH4Cd6(P2O7) 2(P3O10) [6] and Cs2Mo5O2(P2O7)3 · (P3O10) [7].  相似文献   

10.
Chlorothionitrene Complexes of Molybdenum Molybdenum pentachloride reacts with trimer thiazylchloride, (NSCl)3, forming the chlorothionitrene complex \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm Cl}_4 {\rm Mo} = \mathop {\rm N}\limits^ \oplus = \mathop {{\rm SCl}}\limits^ \ominus $\end{document}, in which the chlorothionitrene ligand is to be understood as (NSCl)2? group. I reacts with phosphorylchloride forming the solvate Cl3PO? Mo(Cl4)(NSCl) ( II ) that can also be obtained directly from MoCl5 · OPCl3 and trithiazylchloride. II reacts with chloride ions giving the anionic chlorothionitrene complex [Cl5Mo(NSCl)]? ( III ). Thermal decomposition of I leads to MoNCl3 under SCl2 cleavage, while reaction of I with chloride ions gives [MoNCl4]?. Both reactions prove chlorothionitrene complexes to be excellent precursors for the syntheses of nitrido complexes. The complexes I—III have been characterized by IR spectroscopy.  相似文献   

11.
On Novel Oxoruthenates of the 6 L-Perovskite Type: Ba3SrRu2?xTaxO9 (x = 0.8 and 1.4) with a Comment on Ba3CaRu2O9 Single crystals of the phases Ba3SrRu2?xTaxO9 [(I): x = 0.8 and (II): x = 1.4] and the compound (III): Ba3CaRu2O9 were prepared by a BaCl2 flux and investigated by X-ray methods. (I)–(III) crystallizes with hexagonal symmetry space group P6 2c with lattice constants: (I) a = 6.003 Å; c = 15.227 Å; (II) a = 5.988 Å; c = 15.220 Å and (III) a = 5.891 Å; c = 14.571 Å. The crystal structures of these substances corresponds to the 6 layer perovskites with the stacking sequence (hcc)2. All of them show a so far not described slightly distorted oxygen framework caused by the Sr2+ and Ca2+ ions.  相似文献   

12.
The structures of N‐fluoro­pyridinium tri­fluoro­methane­sulfon­ate, C5H5FN+·CF3O3S, (I), and 1‐fluoro‐2,4,6‐tri­methoxy‐1,3,5‐triazinium hexa­fluoro­antimonate, (C6H9FN3O3)[SbF6], (II), are presented. The N—F bond lengths in (I), a well known electrophilic fluorinating agent, and its novel analogue, (II), are 1.357 (4) and 1.354 (4) Å, respectively.  相似文献   

13.
In the crystal structures of 2‐amino‐5‐chloropyridinium trichloroacetate, C5H6ClN2+·C2Cl3O2, (I), and 2‐methyl‐5‐nitroanilinium trichloroacetate monohydrate, C7H9N2O2+·C2Cl3O2·H2O, (II), the protonated planar 2‐amino‐5‐chloropyridinium [in (I)] and 2‐methyl‐5‐nitroanilinium [in (II)] cations interact with the oppositely charged trichloroacetate anions to form hydrogen‐bonded one‐dimensional chains in (I) and, together with water molecules, a three‐dimensional network in (II). The crystals of (I) exhibit nonlinear optical properties. The second harmonic generation efficiency in relation to potassium dihydrogen phosphate is 0.77. This work demonstrates the usefulness of trichloroacetic acid in crystal engineering for obtaining new materials for nonlinear optics.  相似文献   

14.
The CuII complex bis[hydroxybis(pyridin‐2‐yl)methanesulfonato‐κ3N,O,N′]copper(II) hexahydrate, [Cu(C11H9N2O4S)2]·6H2O, (I), crystallizes in the space group P, compared with P21/c for the anhydrous CoII analogue bis[hydroxybis(pyridin‐2‐yl)methanesulfonato‐κ3N,O,N′]cobalt(II), [Co(C11H9N2O4S)2], (II). However, both molecules sit on a crystallographic inversion centre and are thus very similar in appearance. Jahn–Teller elongation of the Cu—O bonds [2.347 (3) Å in (I) and 2.064 (2) Å in (II)] influences the S—O bond lengths, which are all around 1.455 (3) Å in (I) and 1.436 (2)–1.473 (2) Å in (II).  相似文献   

15.
Phase Equilibrium Diagram of the System KPO3? Pb(PO3)2 The phase equilibrium diagram of the system KPO3? Pb(PO3)2 was determined by means of X-ray, DTA, paper chromatographic and hot-stage microscopic investigations. In addition to the polyphosphates of potassium [KPO3]x and lead [Pb(PO3)2]x it is shown the existence of only two thermodynamically stable potassium lead phosphates: The incongruently melting cyclotriphosphate K4Pb[P3O9]2 and the congruently melting high-molecular polyphosphate [K2Pb(PO3)4]x. The preparation of the cyclotetraphosphate K2Pb[P4O12] in the pure state, obtainable by precipitation from aqueous solution, is not possible by means of thermal interaction of any starting materials.  相似文献   

16.
Synthesis and Crystal Structure of Cobalt(II)-hexaoxodiphosphate(P? P)(4?)-dodecahydrate, Co2P2O6 · 12 H2O Co2P2O6 · 12H2O was obtained by cleavage and simultaneous oxidation of cyclo-hexaphosphate(III) in a solution of ethanol and aqueous ammonia. The crystal structure has been determined (1 898 independent diffractometer data): space group Pbam (No. 55), a = 6.710(2), b = 12.196(2), c = 10.073(3) Å, V = 825.3(1) Å3, Z = 2, R = 0.060. The P2O64? anions show site symmetry C2h and are connected to form chains via cobalt. Two cobalt ions together with two sets of four water molecules and two oxygen atoms of P2O64? form pairs of edge connected octahedra. The common edges are formed by the oxygen atoms of the P2O6 groups.  相似文献   

17.
On the Diphosphates M4(P2O7)3 with M = V, Cr and the Electronic Spectra of Vanadium(III) and Chromium(III) Phosphates Single crystals of ochre colored or dark brown V4(P2O7)3 ( I ) can be obtained by thermal transformation of an amorphous intermediate synthesized from V2O5 and aqueous H3PO3 and H3PO4; brown crystals of Cr4(P2O7)3 ( II ) are formed during thermal decomposition of Cr(PO3)3, C. I and II are isostructural, crystallizing in orthorhombic space group Pbn21 or Pbnm with Z = 4 and lattice constants a = 9.601(2), b = 21.425(5), c = 7.470(4) Å and a = 9.38(1), b = 21.00(4), c = 7.26(2) Å, respectively. Probably due to slight substitution of vanadium(V) for phosphorus atoms (P:Vv ~ 40:1) nonstoichiometic phase composition is found for I prepared at T ~ 1400°C. I and II are characterized by IR and electronic spectroscopy; their electronic spectra are discussed in comparison with those of fourteen other VIII and CrIII phosphates. This includes a discussion of optical properties of CsCrP2O7 changing color from brown to green on change from daylight to artificial light. Some conclusions on the structural arrangement of I and II are drawn.  相似文献   

18.
Reactions of Trichlorophosphazophosphorusdichloride, Cl3P?N? PCl2 P2NCl5 reacts with SbF3 to give P2NCl3F2 from which P2NCl4F is obtained by chlorination. Sulfur oxidizes P2NCl5 to yield SP2NCl5, SO2 to yield SP2NCl5 and OP2NCl5. Reaction product from P2NCl5 and H2S is SPCl2(NH2) besides PCl3. P2NCl5 reacts with (n-C4H9)3P to give (n-C4H9)3P?N? PCl2. All new compounds are characterized by their n.m.r. spectra and their chemical behaviour.  相似文献   

19.
Tris-chloromethyl-phosphine oxide, (ClCH2)3 P?O(I), is obtained by chlorination of (HOCH2)3P?O with PCl5 or (C6H5)3PCl2, and also by oxidation of (CICH2)3P?O and (ClCh2)2(CH3)P?O. High yields of tris-(dialkyloxyphosphonly-methyl)-phosphine oxides, [RO2(O)PCH2]2P?O (II) (R?CH3, C2H5, iso-C3H7, n-C4H9, 2- ethyl-hexyl), tris (alkyloxyphosphinyl-methyl)-phosphine oxides, [R2(O)PCH2]3P?O(R = C6H5, CH3) are obtained by heating tris-chloromethyl-phosphine oxides, [(RO) (R′) (O)PCH2]3P?O (R = C4H9, R′? C6H5) and tris-(oxophosphoranyl-phosphine oxides with phosphites, phosphonites and phosphinites, respectively, at 170–180°C for several hours. Compounds II possess an extraordinarily high absorption capacity. Thus a warm. 2% solution of II (R = C2H5) in benzene solidifies completely on cooling so that no benzene can be poured off. Tris-dihydroxyphosphonyl-methyl)-phosphine oxide, [(HO)2(O)PCH2]3P?O, obtained by hydrolysis of II (R ? C2H5) with refluxing conc. HCl or by thermal decomposition of II (R ? iso-C3H7) at 190°, titrates in aqueous solution as a hexabasic acid with breaks at pH = 4,4 (three equivalents) and pH = 10,7 (three equivalents). It forms crystalline salts with amines, alkali and alkaline earth metals, and is an excellent chelating agent. The 1H- and 31?P-NMR. spectra of all the compounds prepared are discussed.  相似文献   

20.
A centrosymmetric and short O—H?O hydrogen bond was found in isomorphic crystals of potassium hydrogen trans‐glutaconate monohydrate (potassium hydrogen trans‐pent‐2‐ene‐1,5‐dioate, K+·C5H5O4?·H2O), (I), and rubidium hydrogen trans‐glutaconate monohydrate (rubidium hydrogen trans‐pent‐2‐ene‐1,5‐dioate, Rb+·C5H5O4?·H2O), (II). The O?O distance at room temperature is 2.444 (3) Å in (I), and 2.417 (4) Å in (II). The O?O distance for (I) showed no significant decrease at low temperatures.  相似文献   

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