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1.
Sodium Monothiophosphate(V): Crystal Structure and Sodium Ionic Conductivity Anhydrous sodium monothiophosphate Na3PO3S was synthesized along a novel route by freezedrying of the hydrate and subsequent annealing in an argon atmosphere. The crystal structure was determined using X‐ray and neutron powder data. The structural model was found by means of a combined optimization of the difference between the calculated and the measured powder intensities, and of the potential energy of the system. Simultaneous Rietveld refinements of the neutron and X‐ray data (R3c, a = 8.4442(1) Å, c = 11.7412(1) AÅ) resulted in a profile R‐value Rp = 4.86 % and weighted profile R‐value Rwp = 5.86 %. The baricenters of the PO3S tetrahedra are arranged in the sense of a cubic close packing whith the P—S‐bonds oriented in a polar manner parallel to the c axis, and with the PO3‐groups in an eclipsed mutual orientation. The Na‐P‐S‐framework of Na3PO3S is — according to the formulation SPNa3 — related to the LiNbO3‐structure type. The title compound was investigated using solid state NMR spectroscopy. The isotropic chemical shift δiso is 33.4 ppm for the phosphorus nuclei, and 7.7 ppm for the sodium nuclei. For the latter ones, a quadrupole coupling constant QCC = 3.0 MHz and an asymmetry parameter ηQ = 0.40 were determined. The chemical shift tensor of the phosphorus nuclei is characterized by an asymmetry parameter η = 0.43 and an anisotropy Δσ = ‐48.5 ppm. Consequently, phosphorus as well as sodium, is not surrounded axial symmetrically.  相似文献   

2.
The crystal structure of methyl α‐d ‐mannopyranosyl‐(1→3)‐2‐O‐acetyl‐β‐d ‐mannopyranoside monohydrate, C15H26O12·H2O, ( II ), has been determined and the structural parameters for its constituent α‐d ‐mannopyranosyl residue compared with those for methyl α‐d ‐mannopyranoside. Mono‐O‐acetylation appears to promote the crystallization of ( II ), inferred from the difficulty in crystallizing methyl α‐d ‐mannopyranosyl‐(1→3)‐β‐d ‐mannopyranoside despite repeated attempts. The conformational properties of the O‐acetyl side chain in ( II ) are similar to those observed in recent studies of peracetylated mannose‐containing oligosaccharides, having a preferred geometry in which the C2—H2 bond eclipses the C=O bond of the acetyl group. The C2—O2 bond in ( II ) elongates by ~0.02 Å upon O‐acetylation. The phi (?) and psi (ψ) torsion angles that dictate the conformation of the internal O‐glycosidic linkage in ( II ) are similar to those determined recently in aqueous solution by NMR spectroscopy for unacetylated ( II ) using the statistical program MA′AT, with a greater disparity found for ψ (Δ = ~16°) than for ? (Δ = ~6°).  相似文献   

3.
The phosphorus‐sulfur ligand 1‐(methylthio)‐3‐(diphenylphosphino)‐propane (S‐P3) has been synthesized and characterized by 1H NMR and 13C NMR. Reactions of S‐P3 with [PdCl2(PhCN)2] afforded the complexes [PdCl2(S‐P3)] ( I ) and [PdCl2(S‐P3)2] ( II ), in which S‐P3 acts as a bidentate and monodentate ligand, respectively. Compound I crystallizes in monoclinic space group P21/n (No. 14) with cell dimensions: a = 8.589(3), b = 15.051(3), c = 17.100(3)Å, β = 102.91(2)°, V = 2154.7(9)Å3, Z = 4. Likewise, compound II crystallizes in monoclinic space group P21/n (No. 14) with a = 9.993(5), b = 8.613(4), c = 18.721(5)Å, β = 90.18(3)°, V = 1611.3(12)Å3, Z = 2. Compound II has a trans square planar configuration with only the P‐site of the ligand bonded to the palladium atom.  相似文献   

4.
Two polymorphs of a zero‐dimensional (molecular) zinc phosphate with the formula [Zn(2,2′‐bipy)(H2PO4)2]2 have been synthesized by a mild hydrothermal route and their crystal structures were determined by single crystal X‐ray diffraction (triclinic, space group (No. 2), Z = 2, α‐form: a = 8.664(1), b = 8.849(2), c = 10.113(2) Å, α = 97.37(2)°, β = 100.54(2)°, γ = 100.98(2)°, V = 737.5(3) Å3; β‐form: a = 7.5446(15), b = 10.450(2), c = 10.750(2) Å, α = 67.32(3)°, β = 81.67(3)°, γ = 69.29(3)°, V = 731.4(3) Å3). Both structures consist of distorted trigonal‐bipyramidal ZnO3N2 units condensed with PO2(OH)2 tetrahedra through common vertices giving rise to dimers [Zn(2,2′‐bipy)(H2PO4)2]2. The structures are stabilized by extensive inter‐ and intramolecular hydrogen bond interactions. Both modifications display subtle differences in their packing originating from the hydrogen bond interactions as well as π…π interactions between the organic ligands.  相似文献   

5.
The chemically covalent polyethylenimine–siloxane hybrids doped with various amounts of ortho‐phosphoric acid (H3PO4) were prepared and characterized by FTIR, DSC, TGA, and solid‐state NMR spectra. The protonic conduction behavior of these materials was also investigated by means of impedance measurements. These observations indicate that the hydrogen bonding and protonic interactions exist between the dopant H3PO4 and the hybrid host, resulting in an increase in T g of polyethylenimine segments. These hybrids are thermally stable up to 200 °C from TGA analysis. Conductivity studies show an Arrhenius behavior characteristic and the Grotthus‐like proton conduction, and a high conductivity of 10?2–10?3 S cm?1 at 110 °C in dry atmosphere for the hybrid membrane with H3PO4/EI of 0.5. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2135–2144, 2006  相似文献   

6.
A synthetic route to enantiomerically pure (1R,2S)‐1‐phenylphospholane‐2‐carboxylic acid ( 1 ), which is a phosphorus analogue of proline, has been established. A key step is the deprotonation–carboxylation of the 1‐phenylphospholane borane complex 3 by using sBuLi/1,2‐dipiperidinoethane (DPE). Configurational stability of the key intermediate, the amine‐coordinated α‐phosphinoalkyllithium borane complex 4 , was investigated by employing lithiodestannylation–carboxylation of both diastereomers of the 1‐phenyl‐2‐trimethylstannylphospholane borane complex 7 in the presence of several kinds of amines, and as a result, 4 was found to be configurationally labile even at ?100 °C. The key intermediate, the DPE‐coordinated trans‐1‐phenyl‐2‐phospholanyllithium borane complex 9 , was isolated, and the structure was identified by X‐ray crystal structure analysis. This is the first X‐ray crystal structure determined for an α‐monophosphinoalkyllithium borane complex. Remarkably, the alkyllithium complex is monomeric and tricoordinate at the lithium center with a slightly pyramidalized environment, and the existence of a Li? C bond (2.170 Å) has been confirmed. Moreover, 1H–7Li HOESY and 6Li NMR analyses suggested the structure of 9 in solution as well as the existence of an equilibrium between 9 , its cis isomer, and the ion pair 8 at room temperature, which was extremely biased towards 9 at ?100 °C. Finally, 1 was used as a chiral ligand in a palladium‐catalyzed allylic substitution, and the desired product was obtained in high yield with good enantioselectivity.  相似文献   

7.
A symmetric sodium‐ion battery with an aqueous electrolyte is demonstrated; it utilizes the NASICON‐structured Na3MnTi(PO4)3 as both the anode and the cathode. The NASICON‐structured Na3MnTi(PO4)3 possesses two electrochemically active transition metals with the redox couples of Ti4+/Ti3+ and Mn3+/Mn2+ working on the anode and cathode sides, respectively. The symmetric cell based on this bipolar electrode material exhibits a well‐defined voltage plateau centered at about 1.4 V in an aqueous electrolyte with a stable cycle performance and superior rate capability. The advent of aqueous symmetric sodium‐ion battery with high safety and low cost may provide a solution for large‐scale stationary energy storage.  相似文献   

8.
Na‐ion batteries are becoming comparable to Li‐ion batteries because of their similar chemical characteristics and abundant sources of sodium. However, the materials production should be cost‐effective in order to meet the demand for large‐scale application. Here, a series of nanosized high‐performance cathode materials, Na3(VO1?xPO4)2F1+2x (0≤x≤1), has been synthesized by a solvothermal low‐temperature (60–120 °C) strategy without the use of organic ligands or surfactants. The as‐synthesized Na3(VOPO4)2F nanoparticles show the best Na‐storage performance reported so far in terms of both high rate capability (up to 10 C rate) and long cycle stability over 1200 cycles. To the best of our knowledge, the current developed synthetic strategy for Na3(VO1?xPO4)2F1+2x is by far one of the least expensive and energy‐consuming methods, much superior to the conventional high‐temperature solid‐state method.  相似文献   

9.
Herein, we introduce a 4.0 V class high‐voltage cathode material with a newly recognized sodium superionic conductor (NASICON)‐type structure with cubic symmetry (space group P213), Na3V(PO3)3N. We synthesize an N‐doped graphene oxide‐wrapped Na3V(PO3)3N composite with a uniform carbon coating layer, which shows excellent rate performance and outstanding cycling stability. Its air/water stability and all‐climate performance were carefully investigated. A near‐zero volume change (ca. 0.40 %) was observed for the first time based on in situ synchrotron X‐ray diffraction, and the in situ X‐ray absorption spectra revealed the V3.2+/V4.2+ redox reaction with high reversibility. Its 3D sodium diffusion pathways were demonstrated with distinctive low energy barriers. Our results indicate that this high‐voltage NASICON‐type Na3V(PO3)3N composite is a competitive cathode material for sodium‐ion batteries and will receive more attention and studies in the future.  相似文献   

10.
Fast sodium‐ion conductors are key components of Na‐based all‐solid‐state batteries which hold promise for large‐scale storage of electrical power. We report the synthesis, crystal‐structure determination, and Na+‐ion conductivities of six new Na‐ion conductors, the phosphidosilicates Na19Si13P25, Na23Si19P33, Na23Si28P45, Na23Si37P57, LT‐NaSi2P3 and HT‐NaSi2P3, based entirely on earth‐abundant elements. They have SiP4 tetrahedra assembled interpenetrating networks of T3 to T5 supertetrahedral clusters and can be hierarchically assigned to sphalerite‐ or diamond‐type structures. 23Na solid‐state NMR spectra and geometrical pathway analysis show Na+‐ion mobility between the supertetrahedral cluster networks. Electrochemical impedance spectroscopy shows Na+‐ion conductivities up to σ (Na+)=4×10?4 S cm?1. The conductivities increase with the size of the supertetrahedral clusters through dilution of Na+‐ions as the charge density of the anionic networks decreases.  相似文献   

11.
A new type of thio­phene derivative having α‐thio­ketone groups at the 3‐ and 4‐positions, viz. the title compound, C22H20O4S3, has been prepared and studied by NMR spectroscopy and single‐crystal X‐ray diffraction techniques. The mol­ecule is nearly planar, the dihedral angles between the essentially planar thio­phene and benzene rings being 9.4 (1) and 10.6 (1)°. One of the thio­ketone O atoms is involved in an inter­molecular C—H⋯O hydrogen‐bonding inter­action.  相似文献   

12.
Polysulfonylamines. CLXIII. Crystal Structures of Metal Di(methanesulfonyl)amides. 12. The Orthorhombic Double Salt Na2Cs2[(CH3SO2)2N]4·3H2O: A Three‐Dimensional Coordination Polymer Built up from Cesium‐Anion‐Water Layers and Intercalated Sodium Ions The packing arrangement of the three‐dimensional coordination polymer Na2Cs2[(MeSO2)2N]4·3H2O (orthorhombic, space group Pna21, Z′ = 1) is in some respects similar to that of the previously reported sodium‐potassium double salt Na2K2[(MeSO2)2N]4·4H2O (tetragonal, P43212, Z′ = 1/2). In the present structure, four multidentately coordinating independent anions, three independent aquo ligands and two types of cesium cation form monolayer substructures that are associated in pairs to form double layers via a Cs(1)—H2O—Cs(2) motif, thus conferring upon each Cs+ an irregular O8N2 environment drawn from two N, O‐chelating anions, two O, O‐chelating anions and two water molecules. Half of the sodium ions occupy pseudo‐inversion centres situated between the double layers and have an octahedral O6 coordination built up from four anions and two water molecules, whereas the remaining Na+ are intercalated within the double layers in a square‐pyramidal and pseudo‐C2 symmetric O5 environment provided by four anions and the water molecule of the Cs—H2O—Cs motif. The net effect is that each of the four independent anions forms bonds to two Cs+ and two Na+, two independent water molecules are involved in Cs—H2O—Na motifs, and the third water molecule acts as a μ3‐bridging ligand for two Cs+ and one Na+. The crystal cohesion is reinforced by a three‐dimensional network of conventional O—H···O=S and weak C—H···O=S/N hydrogen bonds.  相似文献   

13.
Sodium Trithiophosphate(V): Crystal Structure and Sodium Ionic Conductivity Na3POS3 was synthesized from the corresponding hydrate by freeze‐drying. The crystal structure of Na3POS3 was determined using X‐ray and neutron powder data, and refined applying simultaneous Rietveld refinements of the neutron and X‐ray data (Cmc21, a = 9.5105(1), b = 11.5463(1), c = 5.9323(1)Å, Rp = 5.37 %, Rwp = 4.47 %). The barycenters of the POS3 tetrahedra are arranged in the sense of a hexagonal close packing. The P—O bonds are oriented in a polar manner parallel to the c‐axis, and with the PS3‐groups in an eclipsed mutual orientation. The structure of Na3POS3 is closely related (maximal subgroup) to the one of Ca3CrN3. Above 250 °C, Na3POS3 can be considered as a fast ionic conductor due to its throughout high conductivity.  相似文献   

14.
2,4,8‐Trialkyl‐3‐thia‐1,5‐diazabicyclo[3.2.1]octanes have been obtained by the regioselective and stereoselective cyclocondensation of 1,2‐ethanediamine with aldehydes RCHO (R═Me, Et, Prn, Bun, Pentn) and H2S at molar ratio 1:3:2 at 0°C. The increase in molar ratio of thiomethylation mixture RCHO–H2S (6:4) at 40°C resulted in selective formation of bis‐(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)ethanes. Cyclothiomethylation of aliphatic α,ω‐diamines with aldehydes RCHO (R═Me, Et) and H2S at molar ratio 1:6:4 and at 40°С led to α,ω‐bis(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)alkanes. Stereochemistry of 2,4,8‐trialkyl‐3‐thia‐1,5‐diazabicyclo[3.2.1]octanes have been determined by means of 1H and 13С NMR spectroscopy and further supported by DFT calculations at the B3LYP/6‐31G(d,p) level. The structure of α,ω‐bis(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)alkanes was confirmed by single‐crystal X‐ray diffraction study.  相似文献   

15.
The crystal structure of the title compound, trans‐[Pd(NCS)2(C6H13N3P)2](NCS)2, is one of the few pal­ladium(II) complexes containing two protonated water‐soluble 1,3,5‐tri­aza‐7‐phos­pha­adamantane (PTA) ligands re­ported to date. The compound displays a distorted square‐planar geometry, with the Pd atom on an inversion centre and with the S atoms of the thio­cyanate counter‐ions occupying the axial positions above and below the equatorial plane described by the phosphine and thio­cyanate ligands. Geometric parameters for the formal coordination polyhedron include a Pd—P distance of 2.2940 (8) Å, a Pd—S distance of 2.3509 (8) Å and a P—Pd—S angle of 89.45 (3)°. The effective cone angle for the PTA ligands was calculated as 114.5°.  相似文献   

16.
The development of all‐solid‐state rechargeable batteries is plagued by a large interfacial resistance between a solid cathode and a solid electrolyte that increases with each charge–discharge cycle. The introduction of a plastic–crystal electrolyte interphase between a solid electrolyte and solid cathode particles reduces the interfacial resistance, increases the cycle life, and allows a high rate performance. Comparison of solid‐state sodium cells with 1) solid electrolyte Na3Zr2(Si2PO4) particles versus 2) plastic–crystal electrolyte in the cathode composites shows that the former suffers from a huge irreversible capacity loss on cycling whereas the latter exhibits a dramatically improved electrochemical performance with retention of capacity for over 100 cycles and cycling at 5 C rate. The application of a plastic–crystal electrolyte interphase between a solid electrolyte and a solid cathode may be extended to other all‐solid‐state battery cells.  相似文献   

17.
Semicrystalline poly(bis‐trifluoroethoxymethyl)oxetane, P(B‐3FOx), was prepared by cationic ring‐opening polymerization at ?5 °C with Mn up to 21 kDa. Differences in cooling rates from the melt have substantial effects on crystal phase, percent crystallinity, surface topography, and wetting behavior. DSC and WAXD show that cooling from the melt at slow rates (<5 °C/min) gives α‐P(B‐3FOx) with ΔHf = 22–27 J/g. Quenching from the melt results in β‐P(B‐3FOx) for which a mesophase structure is suggested. β‐P(B‐3FOx) melts at 53 °C followed by recrystallization to α‐P(B‐3FOx). Solution casting from THF results in third phase, γ‐P(B‐3FOx). TM‐AFM and SEM imaging for α‐P(B‐3FOx) showed that cold crystallization at 25 °C brought about increased crystallinity and surface topologies characterized by sharp asperities and lath‐shaped crystals. Spontaneous surface roughening of α‐P(B‐3FOx) results in a discontinuous three‐phase contact line with water and an increase in water sessile drop contact angle from 106° to 136°. The ~30° increase in water contact angle was attributed primarily to a topological change from a relatively smooth surface (Wenzel state) to an asperity‐rich surface yielding a discontinuous three‐phase contact line (composite of Wenzel and Cassie‐Baxter state). The oleophobicity for this polymer, which contains only a single ? CF3 end group on each side chain, compares favorably with more highly fluorinated acrylates. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1022–1034, 2010  相似文献   

18.
The solid and solution structures of a new optically active aminopyridine compound, 2‐[(1S)‐(+)‐10‐camphorsulfonamino]‐6‐aminopyridine [(S)‐csaap], 1 , are reported. Crystal data: space group P21, a = 8.9729 (5), b = 10.9447 (6), c = 36.693 (2) Å, β = 96.435 (1)°, V = 3580.8 (3) Å3, Z = 8, R1 = 0.0673 and wR2 = 0.1600 with I > 2σ(I). This chiral compound shows an unprecedented cocrystallization of four stereoisomers, which are characterized by X‐ray crystallography and NMR spectroscopy.  相似文献   

19.
On Na3PO4: Preparative Investigations, Crystal Structure of High Temperature Form Possibilities for preparing Na3PO4 by solid state reactions have been investigated. The existence of two modifications was proved by means of DTA and X-ray powder methods (temperature range 25–800°C). The phase transition is of first order and occurs reversibly at 325°C. The crystal structure of the high temperature form has been determined using single crystals which have been quenched to room temperature. The structure of H? Na3PO4 contains orientationally disordered PO3?4 anions and derives from the Li3Bi type of structure (Fm3m, a = 742,3 pm).  相似文献   

20.
Crystal Structure of Sodium Dihydrogencyamelurate Tetrahydrate Na[H2(C6N7)O3] · 4 H2O Sodium dihydrogencyamelurate‐tetrahydrate Na[H2(C6N7)O3]·4 H2O was obtained by neutralisation of an aqueous solution, previously prepared by hydrolysis of the polymer melon with sodium hydroxide. The crystal structure was solved by single‐crystal X‐ray diffraction ( a = 6.6345(13), b = 8.7107(17), c = 11.632(2) Å, α = 68.96(3), β = 87.57(3), γ = 68.24(3)°, V = 579.5(2) Å3, Z = 2, R1 = 0.0535, 2095 observed reflections, 230 parameters). Both hydrogen atoms of the dihydrogencyamelurate anion are directly bound to nitrogen atoms of the cyameluric nucleus, thus proving the preference of the keto‐tautomere in salts of cyameluric acid in the solid‐state. The compound forms a layer‐like structure with an extensive hydrogen bonding network.  相似文献   

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