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1.
Five compounds based on [MnMo9O32]6?: (Himi)6[MnMo9O32] ( 1 ) (imi=imidazole), Na2(Himi)4[MnMo9O32] ? 2 H2O ( 2 ), Na3(Himi)3[MnMo9O32] ( 3 ), D ‐NH4Mn2.5[MnMo9O32] ? 11 H2O ( 4 a ), and L ‐NH4Mn2.5[MnMo9O32] ? 11 H2O ( 4 b ) were prepared and characterized. X‐ray crystallographic analysis revealed that compounds 1 and 2 with imidazole molecules as linkers are racemic compounds; compound 3 is a racemic solid solution of Na+ cations and the polyoxoanion [MnMo9O32]6?; and compounds 4 a and 4 b are enantiomers. In compound 4 , the homochiral polyoxoanions [MnMo9O32]6? are connected by Mn2+ cations to form a unique (45 ? 6)(47 ? 68) topology net framework. By adjusting the linkers from imidazole molecules to Na+ and finally Mn2+ cations, the chiral polyoxoanions [MnMo9O32]6? were changed from a racemic compound to a conglomerate. This means that spontaneous resolution can be efficiently realized by connecting homochiral polyoxoanions into one‐dimensional (1D), 2D, and 3D structures, with an emphasis on using appropriate linkers with substantial interaction strength, directionality, and enantioselectivity.  相似文献   

2.
By using cyclohexane‐1,2‐diamine (chxn), Ni(ClO4)2 ? 6H2O and Na3[Mo(CN)8] ? 4H2O, a 3D diamond‐like polymer {[NiII(chxn)2]2[MoIV(CN)8] ? 8H2O}n ( 1 ) was synthesised, whereas the reaction of chxn and Cu(ClO4)2 ? 6H2O with Na3[MV(CN)8] ? 4H2O (M=Mo, W) afforded two isomorphous graphite‐like complexes {[CuII(chxn)2]3[MoV(CN)8]2 ? 2H2O}n ( 2 ) and {[CuII(chxn)2]3[WV(CN)8]2 ? 2H2O}n ( 3 ). When the same synthetic procedure was employed, but replacing Na3[Mo(CN)8] ? 4H2O by (Bu3NH)3[Mo(CN)8] ? 4H2O (Bu3N=tributylamine), {[CuII(chxn)2MoIV(CN)8][CuII(chxn)2] ? 2H2O}n ( 4 ) was obtained. Single‐crystal X‐ray diffraction analyses showed that the framework of 4 is similar to 2 and 3 , except that a discrete [Cu(chxn)2]2+ moiety in 4 possesses large channels of parallel adjacent layers. The experimental results showed that in this system, the diamond‐ or graphite‐like framework was strongly influenced by the inducement of metal ions. The magnetic properties illustrate that the diamagnetic [MoIV(CN)8] bridges mediate very weak antiferromagnetic coupling between the NiII ions in 1 , but lead to the paramagnetic behaviour in 4 because [MoIV(CN)8] weakly coordinates to the CuII ions. The magnetic investigations of 2 and 3 indicate the presence of ferromagnetic coupling between the CuII and WV/MoV ions, and the more diffuse 5d orbitals lead to a stronger magnetic coupling interaction between the WV and CuII ions than between the MoV and CuII ions.  相似文献   

3.
The Crystal Structure of the Sodium Oxohydroxoaluminate Hydrate Na2[Al2O3(OH)2] · 1.5 H2O The crystal structure of the sodium oxohydroxoaluminate hydrate Na2[Al2O3(OH)2] ·s 1.5 H2O (up to now described as Na2O · Al2O3 · 2.5 H2O and Na2O · Al2O3 · 3 H2O, respectively) was solved. The X-ray single crystal diffraction analysis (tetragonal, space group P-421m, a = 10.522(1) Å, c = 5.330(1) Å, Z = 4) results in a polymeric layered structure, consisting of AlO3/2(OH) tetrahedral groups. Between these layers the Na+ ions are situated, which form tetrameric groups of face-linked NaO6 octahedra. The involved O2? ions are due to Al? O? Al bridges, Al? OH groups and water of crystallization. 27Al and 23Na MAS NMR investigations confirm the crystal structure analysis. The relations between the crystallization behaviour of the compound and the constitution of the aluminate anions in the corresponding sodium aluminate solution and in the solid, respectively, are discussed.  相似文献   

4.
Raman and i.r. spectra of solid Na2[B2(O2)2(OH)4]·6H2O (normal, 10B, 11B, and 2H-substituted), Na2[B2(O2)2(OH)4nH2O (n=4, 0), Li2[B2(O2)2(OH)4] and MI2[B2(O2)2(OOH)2(OH)2] (MI= K, Rb, Cs) are reported and the vibrational modes assigned.  相似文献   

5.
Synthesis and Crystal Structure of Na10[P4(NH)6N4](NH2)6(NH3)0.5 with an Adamantane-like Anion [P4(NH)6N4]4? Crystals of Na10[P4(NH)6N4](NH2)6(NH3)0.5 were obtained by the reaction of P3N5 with NaNH2 (molar ratio 1:20) within 5 d at 600°C in autoclaves. The following data characterize X-ray investigations: Fm3 m, Z = 8, a = 15.423(2) Å, Z(F) = 261 with F ≥ 3 σ(F) Z(Variables) = 27, R/Rw = 0.086/0.089 The compound contains the hitherto unknown anion [P4(NH)6N4]4?, which resembles adamantane. The total structure can be described as follows: The centers of gravity of units of [Na8(NH2)6(NH3)]2+ – 8Na+ on the corners of a cube, 6NH2? on the ones of an inscribed octahedron with NH3 in the center – follow the motif of a cubic-closest packed arrangement. Units of [Na12(NH2)6]6+ – 12Na+ on the corners of a cuboctahedron and 6NH2? on the ones of an inscribed octahedron – occupy all octahedral and those of [P4(NH)6N4]4? all tetrahedral sites.  相似文献   

6.
Na6[Ti5O12(OH)2] is the first structurally characterized sodium oxohydroxotitanate. The compound can be prepared via hydrothermal treatment of TiO2 (Anatas) in NaOH (10n ) for 96 h at 250° in an autoclave. The crystal structure of Na6[Ti5O12(OH)2] consists of infinite ribbons [Ti5O12(OH)2]6?. The orthorhombic arrangement has Pbcn (No. 60) symmetry with the lattice constants a=18.668(4) Å, b=6.5333(13) Å, and c=9.829(2) Å.  相似文献   

7.
Thio and Amidothio Derivatives of Diphosphorus(IV) Acid Oxothiodiphosphates(IV) with anions [P2OnS6?n]4? (n = 1–5) are formed by steps wise substitution of thio by oxo ligands in hexathiodiphosphate(4–). Oxidative ammonolysis of thianion leads to amidothio derivatives, [P2(NH2)S5]3? and [P2(NH2)2S4]2?.  相似文献   

8.
Pseudochalkogen Compounds. XVI. Infrared-spectroscopic Investigations of Cyanamidomonophosphates, [PO4?n(NCN)n]3? Infrared spectroscopic investigations of trisodium cyanamidomonophosphates of the general type Na3[PO4?n(NCN)n] · aq (n: 1, 2, 3) are reported. The vibrational spectra of the compounds are confirming very clearly the special position of cyanamidophosphates within the group of substituted phosphates: Cyanamidophosphates are characterized by a full participation of pseudochalkogen groups representing NCN substituents into the mesomeric system of the anions and an only slight shortening of the P? O distances in comparision to [PO4]3?. Characteristic frequencies between 970 and 1150 cm?1 are attributed to v(PO4?nNn)-stretching frequencies. A partial 15N labelling of the monocyanamidophosphate anion, [PO3NCN]3? leads to some splitting or shifting of frequencies being connected with vibrations of the NCN group; isolated v(P? N) stretching frequencies cannot be found.  相似文献   

9.
The complex [Na2(H2O)10][Na(H2O)3]2[MnW6O18(OH)6] · 6H2O was synthesized and studied by mass spectrometry, thermogravimetry, IR spectroscopy, X-ray diffraction. The crystals are monoclinic, space group P21/n, a = 11.698(2), b = 11.670(2), c = 14.652(3) ?, β = 102.52(3)°, V = 1952.7(7) ?3, ρ(calcd.)= 3.45 g/cm3, Z = 2.  相似文献   

10.
Kenji Nomiya  Makoto Miwa 《Polyhedron》1985,4(8):1407-1412
The theory of structural stability, being based on the number of closed loops per MO6 octahedral unit in the polyanion-cage, has been applied to a variety of heteropoly- and isopoly-compounds with previously unreported structures. The discussion includes the prediction of the structure of lacunary Keggin heteropoly-compound, Cs7Na2[PW10O37]·8H2O, recently obtained by Knoth and Harlow, the reinvestigation of mixed-type Keggin polyanions, [SiW9Co3(H2O)3O37]10? and [SiW11CoO39]6?, recently prepared by Pope's group, the interpretation of chemical behaviours of some molybdo- and tungsto-vanadates, the structural stabilities of Jeannin-type [As2W21O69(H2O)]6? polyanion and its related compounds, and some remarks on Weakley-type [X(W5O18)2]n? polyanions and Flynn-Stucky-type [X(Nb6O19)2]n? complexes belonging to the hybrid-complex of polyanion.  相似文献   

11.
Pseudo-chalkogen Compounds. X. Synthesis of Cyanamidophosphates from Phosphoryl Chlorides Cyanamidolytic reactions of the phosphoryl chlorides POCl3 and P203Cl4 ara leading to the new derivatives of ortho- and pyrophosphoric acid POCl3?n(NHCN)n (n = 1, 2) and P2O3CI4?n(NHCN)n (n = 1–4). These compounds may be transformed into cyanamido-mono- and -diphosphates P04?n(NCN)n3? (n = 1, 2) and P207?n(NCN)n4? (n = 1–4) using further reactions with sodium hydroxide. The cyanamidophosphate ions are characterized by their silver and calcium salts, by chromatographic and 31P nmr spectroscopic methods. By the new synthetic route for the first time single compounds of the series of cyanamidophosphates may be prepared without further separating operations.  相似文献   

12.
Oxidation of Intermetallic Phases: Na3[AuO2] from NaAu and Na2O2 The hitherto unknown Na3[AuO2] was prepared in transparent, colourless single crystals from NaAu and Na2O2[1:1; sealed Ag-cylinder, 430°C, 6 d]. The crystal structure (P42/mnm); a = 970.5(1), c = 457.8(1) pm; Z = 4; four-circle diffractometer PW 1100, 333 out of 380 I0(hkl), R = 7.0% and [Rw = 6.5%] was solved. Like KAgO-Type there are planar rings [Na2Au2O4]4?. Na(1) has the uncommon coordinations number 2 . The Effective Coordination Numbers, ECoN, the Mean Fictive Ionic Radii, MEFIR, and the Madelung Part of Lattice Energy, MAPLE, are calculated.  相似文献   

13.
Nonasodium Bis(hexahydroxoaluminate) Trihydroxide Hexahydrate (Na9[Al(OH)6]2(OH)3 · 6H2O) – Crystal Structure, NMR Spectroscopy and Thermal Behaviour The crystal structure of the nonasodium bis(hexahydroxoaluminate) trihydroxide hexahydrate Na9[Al(OH)6]2(OH)3 · 6H2O (4.5 Na2O Al2O3 · 13.5 H2O) (up to now described as 3 Na2O · Al2O3 · 6H2O, 4Na2O · Al2O3 · 13 H2O and [3 Na2O · Al2O3 · 6H2O] [xNaOH · yH2O], respectively) was solved. The X-ray single crystal diffraction analysis (triclinic, space group P1 , a = 8.694(1) Å, b = 11.344(2) Å, c = 11.636(3) Å, α = 74.29(2)°, β = 87.43(2)°, γ = 70.66(2)°, Z = 2) results in a structure, consisting of monomeric [Al(OH)6]3? aluminate anions, which are connected by NaO6 octahedra groups. Furthermore the structure contains both, two hydroxide anions only surrounded by water of crystallization and OH groups of [Al(OH)6]3? aluminate anions and a hydroxide anion involved in three NaO6 coordination octahedra directly and moreover connected with a water molecule by hydrogen bonding. The results of 27Al and 23Na-MAS-NMR investigations, the thermal behaviour of the compound and possible relations between the crystal structure and the conditions of coordination in the corresponding sodium aluminate solution are discussed as well.  相似文献   

14.
We report metathetical reactions of IF5 with series of α,β-trimethylsilylated ethanediolates with increasing numbers of CH3-groups in α- and β-positions. Short lived intermediates IF4[OC2H4?n(CH3)nO]X with X = Si(CH3)3 or IF4 and stable chelates IF3[OC2H4?n(CH3)nO] and IF[OC2H4?n(CH3)nO]2 (n = 0–4) are observed and characterized. Time and temperature dependence of 19F-NMR-spectra in relation to degree of methylation, arrangement and stereo-chemistry are discussed referring to previously published mono- and polynuclear I(V)-compounds containing a series of monodentate alcoholates CH3?n(CH3)nO? and (CH3)3CCH2O? (n = 0,2,3) [1,2] and of bidentate alcoholates ?O(CH2)nO? (n = 2,3,4,5,6,12) [1]. In contrast to aliphatic α,β-diolates the aromatic diolates 1,2-C6H4(O?)2, 1,2-C6Cl4(O?)2 rapidly undergo redox reactions even at low temperatures.  相似文献   

15.
Synthesis and Crystal Structure of Rb8[P4N6(NH)4](NH2)2 with the Adamantane-like Anion [P4N6(NH)4]6? RbNH2 reacts with P3N5 (molar ratio 6:1) at 400°C within 5 d to colourless Rb8[P4N6(NH)4](NH2)2. Suitable crystals for a X-ray structure determination were obtained: The compound contains adamantane-like molecular anions [P4N6(NH)4]6?. Their centres of gravity are arranged in a distorted hexagonal primitive array. All trigonal prisms of this array contain one amide ion. Rubidium ions connect the anions irregularly.  相似文献   

16.
The First Oxocobaltate(II) with Dinuclear Anion: Rb2Na4[Co2O5] and K2Na4[Co2O5] By heating of well ground mixtures of the binary oxides [A2O, Na2O, ?CoO”?, A:Na:Co = 1.00:2.00:1, (A = K, Rb); Ag-tube, 600°C, 14 d] we obtained Rb2Na4[Co2O5] and K2Na4[Co2O5] rough, transparent, red single crystals. We find a new type of structure with the anion [O2CoOCoO2]6?. Space group P42/mnm; a = 634.4 pm, c = 1030.3 pm, Z = 2 (A = K) a = 647.6 pm, c = 1021.1 pm, Z = 2 (A = Rb); four-circle diffractometer data; MoKα -radiation; 360 from 364 I0(hkl), R = 4.34%, Rw = 3.54% (A = K); 361 from 366 I0(hkl), R = 6.54%, Rw = 2.70% (A = Rb). The anion is planar, the CN of Co is 3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.  相似文献   

17.
On the basis of consideration of dissociation, hydration, association, and ligand exchange, the assignment of absorption bands in the electronic spectra of aqueous solutions of the Na4[UO2(O2)CO3)2] complex has been performed. It has been demonstrated that the absorption in the range 190–400 nm is caused by the oxygen atoms of the O22- and CO32- groups and hydration water molecules of dissociated and neutral complex species Na3[UO2(O2)(CO3)2], Na2[UO2(O2)(CO3)2]2–, and Na4[UO2(O2)(CO3)2].  相似文献   

18.
On the Sodium Tetrahydroxoaluminate Chloride Na2[Al(OH)4]Cl The hitherto unknown compound Na2[Al(OH)4]Cl was prepared by crystallisation from a NaCl containing sodium aluminate solution. According to the X-ray single crystal investigation (tetragonal, space group P4/nmm, a = 7.541 Å, c = 5.059 Å, Z = 2) the compound represents the first example of a crystalline hydroxoaluminate with monomeric [Al(OH)4]? anions. Cl? shows a quadratic anti prismatic coordination to 4 Na+ and over hydrogen bonds to 4 O2? while Na+ is octahedrally coordinated by 4 O2? and 2 Cl? (axial). The results of the crystal structure analysis are confirmed by 27Al and 23Na MAS NMR investigations. Na2[Al(OH)4]Cl decomposes at about 200°C without intermediates under formation of β-NaAlO2 and NaCl.  相似文献   

19.
Electrical conductivities of dilute aqueous solutions for unsymmetrical electrolytes of the type 3:1, 1:3, 3:2, 4:1, 1:4, 4:2, 2:4, 1:5 1:6 and 6:1 are reexamined in the framework of the Quint-Viallard conductivity equations, in order to obtain a uniform representation of their conductivities. The molar and equivalent limiting conductances were evaluated with ion association constants, which were treated as adjustable parameters. The derived values were compared with corresponding results from the literature. The following electrolytes are considered: rare earth (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er) halides, perchlorides, nitrates and sulfates; hexamminecobalt and tris-ethylenediaminecobalt halides, perchlorides, nitrates and sulfates; [Ni2(trien)3]Cl4, [Pt(pn)3]Cl4, [Co2(trien)3]Cl6; cyanides K3[Fe(CN)6], K3[Co(CN)6], M3[W(CN)8] with M=Na, K, Rb, Cs; Ca2[Fe(CN)6], K4[Fe(CN)6], K4[Mo(CN)8], K4[W(CN)8], K4[Ru(CN)8], (Me4N)4[Fe(CN)6], (Pr4N)4[Fe(CN)6], K4[Mo(CN)8], (Me4N)4[Mo(CN)8], (Et4N)4[Mo(CN)8] and (Pr4N)4[Mo(CN)8]; phosphates Na4P2O7, Na4P4O12, Na5P3O10, Na6P6O18 and (Me4N)4P4O12.  相似文献   

20.
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   

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