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1.
[C6N2H18]2[Mo5O15(HPO4)2]·H2O的水热合成与结构表征   总被引:6,自引:0,他引:6  
通过水热法合成了一个新化合物[C6N2H18]2[Mo5O15(HPO4)2]·H2O,并通过IR光谱、ICP、元素分析、差热与热重分析和X射线单晶衍射分析等手段进行了表征.结果表明,晶体属三方晶系,P3(2)21空间群,a=1.1231(1)nm,c=2.2802(5)nm,V=2.4911(7)nm3,Dx=2.835Mg/m3,Z=6,最后的一致性因子R=0.0227,wR=0.0675.阴离子中Mo5O15构成一环状结构,2个HPO4一个连在环的下方,一个连在环的上方,形成类似于“飞碟”状的结构,阳离子为2个质子化的四甲基乙二胺.  相似文献   

2.
Single crystals of a new beta-octamolybdate salt containing protonated 1,4-diazabicyclo[2.2.2]octane cations were prepared under mild hydrothermal conditions. This compound, [C6H13N2]2[C6H14N2][Mo8O26], was then used as a starting material in the synthesis of [C6H13N2]6[Mo16O53F2].4H2O, which contains previously unreported [Mo16O53F2]12- anions. The structure-directing properties of gamma-[Mo8O26]4-, a likely intermediate in this pH-dependent transformation, are responsible for the site selection of the fluoride incorporation. [Mo16O53F2]12-, the largest reported polyoxofluoromolybdate cluster, expands upon the limited number of such anions in the literature. The structures of both compounds were determined using single-crystal X-ray diffraction.  相似文献   

3.
The title complex (enH2){NH4[Co(en)3][Mo2O7(C2O4)]}2·2H2O (C18H70Co2Mo4- N16O24, Mr = 1396.52) was obtained under hydrothermal conditions and its crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c with a = 17.8023(8), b = 7.7527(4), c = 16.9781(4)A,β= 103.878(7)°, V = 2274.8(2) A3, Dc = 2.039 g/cm3, Z = 2,μ(MoKα) = 1.878 mm-1 and F(000) = 1408. The final R = 0.0410 and Wr = 0.1070 for 4065 observed reflections with I≥2σ(I). The crystal structure is composed of bi- nuclear [Mo2O7(C2O4)]4- anions, complex [Co(en)3]2+ cations, protonated ethylenediamine cations, ammonium cations and crystal water molecules, which are held together into a three-dimensional network via hydrogen-bonding interactions. The binuclear structure of [Mo2O7(C2O4)]4- consist of one MoO4 and one MoO6 octahedra through sharing a bridging oxygen atom, where the oxalate ligand acts as a bidentate ligand coordinating to the octahedral molybdenum atom though two deprotonated corboxylate groups.  相似文献   

4.
Two molybdophosphate compounds,[Ni(bim)3]2[H2P2Mo5O23]·2H2O 1 and [Zn(bpy)2]2[Zn(bpy)(H2O)]2Zn[Mo6O12(OH)3(HPO4)4]2·9H2O 2 (bim = 2,2'-biimidazole,bpy = 2,2'-dipyridyl),have been synthesized under hydrothermal conditions and structurally characterized by elemental analysis,TG,and IR. The single-crystal X-ray analysis exhibits that 1 consists of one [H2P2Mo5O23]4-,two [Ni(bim)3]2+ cations and two lattice water molecules,while 2 is constructed from one sandwich-type [ZnP4Mo6] anion modified by four Zn-bpy complexes and nine lattice water molecules. The electrochemical behaviors of compounds 1 and 2 have been studied in detail based on solid bulk modified carbon paste electrodes of compound (CPEs).  相似文献   

5.
<正> Guanidinium bis (o - aminophenylarsenic) hexamolybdate belongs to monoclinic space group P21/c,with a=10. 217(2),b= 18. 870(2),c= 10. 939(2)A,β = 102. 82(3)°,Z = 2,V=2056. 4A3,and Dc=2. 477 g·cm-3. Each molecule contains one [(o-NH2C6H4As)2Mo6O24]4- anion and four CN3H6+ cations. In the anion,six distorted MoO6 octahedra are connected with edges-sharing to form a six-membered Mo ring which is capped above and below by two o - aminophenylarsenic groups. There is half a molecule in an asymmetric unit. It is interesting that both phenyl planes are almost perpendicular to the plane of the Mo atoms. The structure of the anion is similar to that of [ (CH3 As)2Mo6O24]4-,[(n-C3H7As)2Mo6O24]4- or [(C6H5CH2As)2Mo6O24]4-. This is the first example of this type of compounds in which the As atom is directly connected to a substituted phenyl group.  相似文献   

6.
Shivaiah V  Das SK 《Inorganic chemistry》2005,44(21):7313-7315
A supramolecular copper-aqua-crown ether complex, [Cu(II)(H2O)4(dibenzo-24-crown-8]2+ (1c) is stabilized with a Lindqvist-type polyoxometalate anion, [Mo(VI)6O19]2- (1a), in an ion-pair compound [Cu(II)(H2O)4(dibenzo-24-crown-8][Mo(VI6O19] identical with [1c][1a] identical with 1. In the crystal, 1c and 1a assemble to a chainlike structure in which each polyoxoanion 1a is sandwiched by two 1c cations. 1c is a structurally characterized dibenzo-24-crown-8 (a larger-cavity crown ether) supramolecular complex that shows encapsulation of a small cation at the center of its internal cavity, and compound 1 represents a unique example of a first-row transition metal-crown ether inclusion complex that interacts with a polyoxometalate anion.  相似文献   

7.
Organic-inorganic hybrid materials based on polyoxometalate building blocks with capping La3+ ions and bidentate oxygenated ligands have been obtained by reaction at room temperature of the [epsilon-PMo12O36(OH)4[La(H2O)4]]5+ polyoxocation with glutarate (C5H6O(2)(2-)) and squarate (C4O(4)(2-)) organic ligands. [epsilon-PMo12O37(OH)3[La(H2O)4(C5H6O4)0.5]4].21 H2O (1) and [epsilon-PMo12O39(OH)[La(H2O)6]2-[La(H2O)5(C4O4)0.5]2].17 H2O (2) form unprecedented 1D chains built from alternating polyoxocations and organic ligands connected through LaO links. The structures of these materials are compared to the 2D hybrid organic-inorganic framework [NC4H12]2-[Mo22O52(OH)18[La(H2O)4]2[La(CH3CO2)2]4].8H2O (3) isolated from the hydrothermal reaction of elemental precursors (MoO(4)(2-), Mo, La3+) in acetate buffer. Compound 3 is built from previously undescribed polyoxometalate units with twenty-two MoV centers capped by six La3+ ions, four of which are bridged by acetate ligands.  相似文献   

8.
The novel spherical cluster-compound K2Na6[K20 [symbol: see text] Mo80-V22O282(SO4)12(H2O)66]. approximately 140H2O 1 has been obtained in a 'one-pot' reaction and exhibits several remarkable structural features: 30 open shell centers, i.e. 8 Mov and 22 VIV spanning an icosidodecahedron, the incorporation of 20 K+ cations capping 20 appropriate [M6O6] pores/rings present at the surface of the spherical cluster-anion, and an encapsulated aggregate of water molecules.  相似文献   

9.
The electrochemistry of the Dawson-like sulfite polyoxometalate anion alpha-[Mo18O54(SO3)2]6-, derived from the TEAH6{alpha-[Mo18O54(SO3)2]} salt (TEAH+ is the triethanolammonium cation; pKa=7.8), has been investigated in aqueous media using cyclic and rotated disk voltammetry at glassy carbon electrodes and bulk electrolysis, with a focus on the pH-dependence for oxidation to alpha-[Mo18O54(SO3)2]4-. In buffered media at pH>or=4, the cyclic voltammetric response for alpha-[Mo18O54(SO3)2]6- reveals two partially resolved one-electron oxidation processes corresponding to the sequential generation of alpha-[Mo18O54(SO3)2]5- and alpha-[Mo18O54(SO3)2]4-. At lower pH, using electrolytes containing sulfuric acid, the two waves coalesce but the individual apparent E0' reversible formal potential values for the two processes can be extracted down to pH 2 by assuming that reversible protonation accompanies fast electron transfer. The results for 2相似文献   

10.
The face-sharing bioctahedral molybdenum(VI) oxide fluoride anion [Mo2O6F3]3- has been isolated in the new compound [Cu(3-apy)4]3(Mo2O6F3)2 (3-apy = 3-aminopyridine) and has been characterized by experimental and computational techniques. Single-crystal X-ray diffraction studies show that the structure of the [Mo2O6F3]3- anion resembles two distorted face-sharing octahedra, each with three short terminal metal-ligand bonds and three long metal-ligand-metal bridging interactions. Aspects of the electronic structure, as well as geometric comparisons of the bond lengths and angles in [Mo2O6F3]3- with those in the similarly distorted [MoO3F3]3- anion, suggest that the six terminal ligand positions of the confacial bioctahedra are occupied exclusively by oxide ligands and that the three bridging sites are occupied by fluorides. Crystal data for [Cu(3-apy)4]3(Mo2O6F3)2: trigonal space group R3 (No. 148) with hexagonal axes of a = 13.881(1) A and c = 31.783(3) A (Z = 3).  相似文献   

11.
Synthesis of the cyclic aluminatophosphazene ring N(PCl2NMe)2AlMeCl (5) has been achieved via a skeletal transmetalation reaction between AlMe3 and the boratophosphazene N(PCl2NMe)2BCl2 (1). Reaction of 5 with various halogenated Lewis acids such as GaCl3 yielded the fully chlorinated aluminum heterocycle N(PCl2NMe)2AlCl2 (8) through a methyl-halogen exchange process. In contrast, treatment of 5 with excess AlMe3 resulted in complete methylation at aluminum to give N(PCl2NMe)2AlMe2 (6). Compound 5 was reacted with various Ag+ salts with weakly coordinating anions, including Ag[OSO2CF3], which afforded the triflate-substituted heterocycle N(PCl2NMe)2AlMe(OSO2CF3) (9). The reaction of 5 with Ag[BF4] surprisingly produced the previously known fluorinated boratophosphazene N(PCl2NMe)2BF2 (10). The transformation of 1 to 5 and then to 10 represents a rare, formally reversible, skeletal transmetalation process involving boron and aluminum. Treatment of 5 with Ag[PF6] led to the insertion of phosphorus in place of aluminum to form the novel zwitterionic fluorinated phosphorus(V) heterocycle N(PCl2NMe)2PF4 (11). The ethyl-substituted aluminatophosphazene N(PCl2NMe)2AlMeEt (14) reacted cleanly with a 1:1 mixture of [Ph3C][B(C6F5)4] and THF to give the novel donor-stabilized alumazine-phosphazene hybrid cation, [7.THF]+, as the [B(C6F5)4]- salt [N(PCl2NMe)2AlMe.THF][B(C6F5)4] (15).  相似文献   

12.
A new complex constructed from a unit with two As3O6 rings capping Anderson-type moieties,[Ni(en)2(H2O)2]2[(NiO6)Mo6O18(As3O3)2]·2H2O(1,en = ethylenediamine),has been hydrothermally synthesized and characterized by IR,single-crystal X-ray diffraction and thermogra-vimetric analysis.The compound crystallizes in triclinic,space group P1 with a = 9.1230(16),b = 11.8078(9),c = 12.2111(9) ,α = 114.5210(10),β = 98.0350(10),γ = 100.0320(10)o,Mr = 2029.80,C8H44As6Mo6N8Ni3O36,V = 1145.0(2) 3,Dc = 2.944 g/cm3,Z = 1,GOF = 0.997,μ = 7.203 mm-1,F(000) = 970,R = 0.0352 and wR = 0.1019.Compound 1 consists of an Anderson-type capped by a two-ring(As3O6) unit [(NiO6)Mo6O18(As3O3)2]4-,two six-coordinate [Ni(en)2(H2O)2]2+ cations and two water molecules.  相似文献   

13.
A comparative study of the reactivity of isolobal rhenium and molybdenum carbonylmetallates containing a borole, in [Re(eta5-C4H4BPh)(CO)3]- (2), a boratanaphthalene, in [Mo(eta5-2,4-MeC9H6BMe)(CO)3]- (4a) and [Mo(eta5-2,4-MeC9H6BNi-Pr2)(CO)3]- (4b), a boratabenzene, in [Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3]- (6) or a dimethylaminocyclopentadienyl ligand, in [Mo(eta5-C5H4NMe2)(CO)3]- (7), toward palladium(II), gold(I), mercury(II) and platinum(II) complexes has allowed an evaluation of the role of these pi-bonded ligands on the structures and unprecedented coordination modes observed in the resulting metal-metal bonded, heterometallic complexes. The new metallate 6 was reacted with [AuCl(PPh3)], and with 1 or 2 equiv. HgCl2, which afforded the new heterodinuclear complexes [Au{Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3}(PPh3)] (Mo-Au) (10) and [Hg{Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3}Cl] (Hg-Mo) (11) and the heterometallic chain complex [Hg{Mo(eta5-3,5-Me2C5H3BNi-Pr2)(CO)3}2] (Mo-Hg-Mo) (12), respectively. Reactions of the new metallate 7 with HgCl2, trans-[PtCl2(CNt-Bu)2] and trans-[PtCl2(NCPh)2] yielded the heterodinuclear complex [Hg{Mo(eta5-C5H4NMe2)(CO)3}Cl] (Mo-Hg) (15), the heterotrinuclear chain complexes trans-[Pt{Mo(eta5-C5H4NMe2)(CO)3}2(CNt-Bu)2] (Mo-Pt-Mo) (16) and trans-[Pt{Mo(eta5-C5H4NMe2)(CO)3}2(NCPh)2] (Mo-Pt-Mo) (17), the mononuclear complex [Mo(eta5-C5H4NMe2)(CO)3Cl] (18), the lozenge-type cluster [Mo2Pt2(eta5-C5H4NMe2)2(CO)8] (19) and the heterodinuclear complex [[upper bond 1 start]Pt{Mo(eta5-C5H4N[upper bond 1 end]Me2)(CO)3}(NCPh)Cl](Mo-Pt) (20), respectively. The complexes 11, 16, 17.2THF, 18 and 20 have been structurally characterized by X-ray diffraction and 20 differs from all other compounds in that the dimethylaminocyclopentadienyl ligand forms a bridge between the metals.  相似文献   

14.
Hexaalkylguanidinium and 2-(dialkylamino)-1,3-dimethylimidazolinium trimethyldifluorosiliconates, precursors for two stable hexaalkylguanidinium perfluoroalkoxides, were synthesized by treating commercially available bis(dialkylamino)difluoromethane derivatives with (dialkylamino)trimethylsilanes in aprotic media. With hexamethylguanidinium pentafluoroethoxide the introduction of the lipophilic and electronegative C2F5O group was straightforwardly achieved in the case of primary and secondary alkyl triflates to furnish the respective fluorinated ethers. The molecular structures of [(CH2NMe)2C(NEt2)]+[Me3SiF2]- and [C(NMe2)3]+F-*6CH2Cl2 were determined, showing in the latter case a fluoride anion octahedrally coordinated by six methylene chloride molecules via hydrogen bridges with a F...H distance of 205 pm (C...F distance 270.0(3) pm).  相似文献   

15.
1 INTRODUCTION Owing to their unusual topological properties and economically important applications in many fields, such as catalysis, biology, materials science and mag- netochemistry[1~3], polyoxometalates (POMs) have aroused particular interest for a long time[4~6]. But the investigation in their capability and application are relatively less carried on. Even though some POMs have been put into practice, the mechanism of the function of POMs remains incompletely understood. Thus,…  相似文献   

16.
A novel compound, (4,4'-Hbpy)3[NaMo8O26](4,4'-bpy)2(H2O)4 1 (bpy = bipydine),was synthesized by the hydrothermal method. Single-crystal X-ray diffraction shows that compound 1 belongs to the monoclinic system, space group C2/m with a = 19.1921(5), b = 18.6931(6), c = 9.3821 (3) (A), β = 104.8020(11)°, V = 3254.22(17) (A)3, C50H51Mo8N10NaO30, Mr = 2062.52, Z = 2,F(000) = 2016,μ = 1.591 mm- 1 and Dc = 2.105 g/cm3. The final R = 0.0283 and wR = 0.0912 for 3118 observed reflections (I > 2σ(Ⅰ)). Compound 1 contains the β-[Mo8O26]4- anion, sodium ion, 4,4'-bpy and lattice crystalline water molecules. The β-[Mo8O26] units link the sodium ion to form a chain structure. The infinitechains of [Na(Mo8O26)]3- blocks are surrounded by protonized 4,4'-bpy cations,4,4'-bpy and lattice crystalline water molecules. The 2D-IR correlation spectroscopy study indicates that the stretching vibrations of Mo=O occur more preferentially due to the thermal effect. The TGA analysis shows that compound 1 has high thermal stability.  相似文献   

17.
(H_2en)_2[Se_2Mo_5O_(21)]2H_2O的水热合成、晶体结构与光谱研究   总被引:4,自引:0,他引:4  
在水热条件下, 以SeO2、V2O5、MoO3、K2CO3、en(乙二胺)作为起始原料, 得到了标题化合物(H2en)2[Se2Mo5O21]2H2O, 利用IR、UV、荧光光谱、单晶-X射线衍射等方法对其进行了表征。结构测定表明, 该化合物属于正交晶系, 空间群: P212121, 化学式: C4H24- Mo5N4O23Se2, 晶胞参数: a = 12.1386(7), b = 17.7118(8), c =11.7092(5) ? V = 2517.4(2) ?, Z = 4, Dc = 2.987 g/cm3, Mr = 1133.89, m = 5.419 mm-1, F(000) = 2144, 最终结构偏离因子R = 0.0285, wR = 0.0400, S = 0.904。该化合物由2个双质子化的en、2个H2O分子以及杂多阴离子[Se2Mo5O21]4-组成。其中,杂多阴离子由5个畸变的MoO6八面体以共边或共顶点形式连接构成一个平面骨架; 2个畸变的SeO3四面体和MoO6八面体以共顶点形式连接, 且位于平面的两侧;质子化的en位于4个[Se2Mo5O21]4-离子围成的四面体空位中, 与杂多阴离子和水分子通过氢键连接成无限三维结构。最后我们用B3LYP方法研究了阴离子簇的电子结构。  相似文献   

18.
A computational study of the isomers of tetrafluorinated [2.2]cyclophanes persubstituted in one ring, namely F4-[2.2]paracyclophane (4), F4-anti-[2.2]metacyclophane (5a), F4-syn-[2.2]metacyclophane (5b), and F4-[2.2]metaparacyclophane (6a and 6b), was carried out. The effects of fluorination on the geometries, relative energies, local and global aromaticity, and strain energies of the bridges and rings were investigated. An analysis of the electron density by B3PW91/6-31+G(d,p), B3LYP/6-31+G(d,p), and MP2/6-31+G(d,p) was carried out using the natural bond orbitals (NBO), natural steric analysis (NSA), and atoms in molecules (AIM) methods. The analysis of frontier molecular orbitals (MOs) was also employed. The results indicated that the molecular structure of [2.2]paracyclophane is the most affected by the fluorination. Isodesmic reactions showed that the fluorinated rings are more strained than the nonfluorinated ones. The NICS, HOMA, and PDI criteria evidenced that the fluorination affects the aromaticity of both the fluorinated and the nonfluorinated rings. The NBO and NSA analyses gave an indication that the fluorination increases not only the number of through-space interactions but also their magnitude. The AIM analysis suggested that the through-space interactions are restricted to the F4-[2.2]metacyclophanes. In addition, the atomic properties, computed over the atomic basins, gave evidence that not only the substitution, but also the position of the bridges could affect the atomic charges, the first atomic moments, and the atomic volumes.  相似文献   

19.
The electrocrystallization of fluorinated bis(2,2'-difluoropropylenedithio)tetrathiafulvalene (1) in the presence of linear (ICl2-, IBr2-, I2Br-) or cluster ([Mo6Cl14]2-) anions affords 1:1 and 2:1 cation radical salts such as [1][ICl2] and [1]2[Mo6Cl14].(CH3CN)2. In both salts, the 1*+ radical ion adopts a boat conformation and envelops the anion through C-H...Hal(anion) (Hal(anion) = Cl, Br, I) hydrogen bonds. This demonstrates the activating role of the neighboring electron-withdrawing CF2 moieties in the stabilization of bi- or trimolecular neutral entities. With smaller linear anions, fluorine segregation controls the solid-state associations of the bimolecular [1]*+[X] entities, and gives rise to layered materials with a limited overlap interaction between the open-shell organic cations and magnetic spin chain behavior. With the larger [Mo6Cl14]2 ions, a strong overlap interaction between radical cations gives rise to diamagnetic [1]2(2+) dimers, which alternate with the cluster anions to form hybrid organic/inorganic ...[1]2(2+)[Mo6Cl14]2... chains. This behavior is also observed in [2]2(2+)[Mo6Cl14]2-.(CH2Cl2)2, in which compound 2 is the unsymmetrically substituted (ethylenedithio)(2,2'-difluoropropylenedithio)tetrathiafulvalene. On the other hand, the unsymmetrically substituted 2,2'-difluoropropylenedithiotetrathiafulvalene (3) affords a mixed-valence 4:1 salt with [Mo6Cl14]2, which is formulated as [3]4[Mo6Cl14].(CH3CN)2. This semiconducting salt is characterized by the coexistence of both the fluorine/fluorine segregation (with solvent inclusion) and the organic/inorganic segregation (with delocalized overlap interactions). Both Csp2-H...Cl and Csp3-H...Cl hydrogen bonds facilitate the stabilization of the organic/inorganic interface and the presence of conducting organic slabs.  相似文献   

20.
<正> Crystal of the title complex [(n-C4H9)4N]3[Mo6O18(N2C6H3-2,4-(NO2)2](Mr= 1710. 5) is orthorhombic with space group P21cn (Pna21), a = 17. 304(3), b = 17.580(2), c=24. 355(4) (?), V = 7409(2)(?)3, Z = 4, Dc=1. 60g/ cm3, μ=10. 29cm-1, F (000) = 3647. The structural solutions and refinements based on 3900 reflections (I≥3σ(I)) converged at R = 0. 0575, Rw =0. 0498. The atoms of Mo(3), Mo(4), O(1), O(5), O(9), O(11) and the [N2C6H3-2,4-(NO2)2] unit in the complex anion locate approximately in a plane about which the complex anion is nearly symmetrical.  相似文献   

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