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1.
1INTRODUCTIONPolyoxometallates(POM)areofgreatinterestnotonlyfortheirstructuralvarietybutalsotheirunexpectedproperties[1,2].Theseinorganicanionshavebeenwidelyinvestigatedasdiversascatalysis,biology,medicine,magnetochemistryandmaterialscience[3~7].Thestudiesonthecoordinatedpoly-oxometallateswithorganicligandsmighthelptounderstandtherolesofpolyoxometallatesoncatalysis.Todate,aseriesofoctamolybdateswhichcanbedescribedas[Mo8O26X2]2n-4(nisthenormalchargeofthecoordinatedbaseX)havebeenreport…  相似文献   

2.
A novel compound, (Himi)(H(3)O) [Cu(imi)(2)](2)[P(2)Mo(5)O(23)].H(2)O 1 (imi=imidazole), was synthesized by hydrothermal method and characterized by X-ray single analysis, ESR spectrum, one-dimensional (1D) infrared spectroscopy and two-dimensional (2D) correlation infrared spectroscopy under thermal and magnetism perturbation. Crystal data for the compound 1: orthorhombic system, space group Pnma, a = 14.580(3)A, b = 21.073(4)A, c = 16.664(3)A, Z = 4. It consists of the Mo-Cu building-blocks [Cu(imi)(4)](2)[P(2)Mo(5)O(23)](2-), protonated imidazole cations and water molecules. In the Mo-Cu building-blocks, [Mo(5)P(2)O(23)](6-) clusters are linked by {Cu(imi)(4)}(2+) group to form a two-dimension parallelogram griddling structure. From the 2D IR correlation spectroscopy analyses, it is discovered that the intensity changes of Mo=O and P-O band are sensitive to the temperature variation, whereas the Mo-O bond linking to Cu(2+) can be remarkably affected by the magnetism variation. Furthermore, the intensity changes of P-O bands occur prior to that of the Mo=O band during the temperature elevation.  相似文献   

3.
Three novel inorganic-organic hybrid materials, [Cu(imi)2(H2O)(MoO4)]n 1, [Cuz(imi)3(MoO4)E]n.nH2O 2 and [Cu3(imi)2(OH)2(MoO4)2]n 3 (imi = imidazole), were synthesized and characterized by X-ray single-crystal structure determination. 1 crystallizes in orthorhombic, space group Pca21 with a = 13.382(4), b = 8.527(2), c = 9.622(3)A, V = 1098.0(5) A^3 Z = 4, C6H10CuMoN4O5, Mr = 377.66, Dc = 2.285 g/cm^3, F(000) = 740,μ(MoKa) = 3.095 mm^-1, the final R = 0.0256 and wR = 0.0722 for 1896 observed reflections with I 〉 2σ(I). 2 crystallizes in monoclinic, space group P2t/c with a= 11.170(2), b = 7.8244(15), c = 22.631(4)A, β = 115.790(7)°, V = 1780.9(6)A^3 Z = 4, C9H14Cu2Mo2N6O9, Mr = 669.24, Dc= 2.496 g/cm^3, F(000)=1295,μ(MoKa) = 3.792 mm^-1, the final R = 0.0225 and wR = 0.0615 for 3838 observed reflections with I 〉 2σ(I). 3 crystallizes in monoclinic, space group P21/c with a = 5.5599(19), b = 23.771(8), c = 7.3044(18)A , β = 129.356(16)°, V = 746.5(4)A^3, Z = 2, C6H10Cu3Mo2N4O10, Mr = 680.71, Dc = 3.029 g/cm^3, F(000) = 650,μ(MoKa) = 5.900 mm^-1, the final R = 0.0215 and wR = 0.0524 for 1620 observed reflections with I 〉 2σ(I).  相似文献   

4.
1 INTRODUCTION The polymeric metal complexes with extended structures are of great interest because of their useful chemical or physical properties[1]. Due to the noticeable fact that the aromatic polycarboxylate can provide versatile coordination mode and the non-coplanar structure of the carboxylate groups and the benzene rings, a lot of efforts in this field have been particularly directed to the preparation of aromatic polycarboxylate (such as phthalate, tere- phthalate and isophthal…  相似文献   

5.
1 INTRODUCTION The contemporary studies on POMs reveal theirspecial properties which endow these materials withwide range of applications, such as catalysis, medi-cine[1], material science[2], etc. Current research inte-rest mainly focuses on the development of solid ma-terials with unusual structural complexity and con-comitant diversity of applicable properties. A series ofmolybdate oxide phases have been synthesized, inwhich the polymolybdate anions are linked intoinfinite 1-, 2- or 3…  相似文献   

6.
1 INTRODUCTIONThestudiesonorganicpolyoxometallateshelptounderstandtherolesofpolyox ometallatesoncatalysis.Aseriesofoctamolybdateswithdescription〔Mo8O2 6X2 〕2n -4(nisthenormalchargeofthecoordinatedbaseX)havebeenreportedinliteratures .Theirstructuresoftheα ,β ,γ …  相似文献   

7.
潘国华  庄伯涛 《结构化学》2001,20(5):384-386
1 INTRODUCTION In 1984, thiolate ligand was successfully introduced into molybdenum carbonyl compound by the reaction of Mo(CO)6 with [Et4N]SR( R = C6H5, But) in a moderate condition[1]. From then on, a series of dinuclear molybdenum(0) carbonyl thiolate compounds have been synthesized and characterized by using a variety of thiolate ligands in our research group. It was found that a planar Mo2S2 unit is in the compound [Et4N]2[Mo2(CO)8(SC6H4-CH_3-p)2][2] (2) and a "butterfly" t…  相似文献   

8.
Reaction of Mo(CO)6 with p-H3CO-C6H4SNa and Et4NCl · H2O in CH3CN afforded a dinuclear molybdenum(0) compound [Et4N]2[Mo2 (CO)8 (SC6H4-OCH3-p)2] (1). The crystal structure was determined by X-ray diffraction. The crystallographic data: C38H54Mo2N2O10S2, Mr = 954.87, triclinic, P-1, a = 11.348 (7), b =11.616(5), c=10.065(7) A, a=113.86(4), β=111.39(5), γ=91.92(5)°, V=1104.0(1) A3, Z=1, Dc=1.44 g/cm3, F(000)=492, μ=7.0cm-1, Final R=0. 046 and Rw=0. 049 for 2657 reflections with I>3. Oσ(I). The X-ray structure analysis revealed that the Mo2S2 core of 1 is planar. The geometry around each Mo atom is a distorted octahedron, the two octahedrons form an edge-sharing bioctahedron. The bond. In addition, the 95Mo NMR chemical shift of 1 is discussed.  相似文献   

9.
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   

10.
One new polyoxometalate compound connected via nickel/potassium cations, H8K{[Ni(H2O)5]2(H2Mo1.80W10.20O42)}Cl3·16H2O 1, was prepared and characterized by elemental analysis and IR spectroscopy. Single-crystal X-ray diffraction analysis results reveal that clusters of [Ni(H2O)5]2(H2Mo1.80W10.20O42)}6-in compound 1 are linked by potassium cations to form one- dimiensional chains, based on which a three-dimensional network is further constructed via the hydrogen bonds of O…O and O…Cl. Magnetic measurements show that compound 1 has para- magnetic properties. Crystal data: H62Cl3KMo1.80Ni2O68W10.20, Mr = 3461.33, monoclinic, space group C2/c, a = 18.9291(19), b = 16.6758(17), c = 19.1064(19), β = 106.6880(10)°, V = 5777.1(10)3, Z = 4, Dc = 3.980 g/cm3, F(000) = 6250, μ = 21.574 mm?1, R = 0.0579 and wR = 0.1623 (I > 2σ(I)).  相似文献   

11.
Reaction of Mo (CO)6 with p-Cl-C6H4SNa and Et4NCl · H2O in CH3CN afforded a dinuclear molybdenum (0) compound [Et4N]2 [Mo2 (CO)8 (SC6H4-Cl-p)2] (1). The crystal structure was determined by X-ray diffraction. The crystallographic data: C36H48Cl2Mo2N2O8S2, Mr= 963.71, monoclinie, P21/c, a=9. 269(4),b=13.750(3), c=17.466(6) A ;β=104.84(3)°; V=2151.8(3) A3; Z=2; Dc=1.49 g/cm3; F(000)=984; μ=8.3 cm-1; MoKα radiation (λ=0. 71073A ); Final R = 0. 055 and Rw=0. 065 for 3287 reflections with I>3. 0σ(I). The X-ray structure analysis revealed that the Mo2S2 core is planar. The geometry around each Mo atom is a distance is 4. 014(2) A , and this obviously indicates the absence of Mo-Mo bond.  相似文献   

12.
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   

13.
The title compound, [Ni(C8N3H7)3]4[Mo8O26]2·6H2O 1, has been synthesized from the reaction of 2-(1H-pyrazol-3-yl)-pyridine (L) with (NH4)2MoO4·2H2O and NiCl2·6H2O. Elemental analysis, IR, UV spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the compound. Crystal data: C96H96Mo16N36Ni4O58, Mr = 4451.97, monoclinic system, space group P21/n, a = 20.846(5), b = 14.825(5), c = 23.122(5) A ,β= 91.594(5)°, V = 7143(3)A^3, Z = 2, F(000) = 4344, Dc = 2.070 g/cm^3,μ = 1.968 mm^-1, R = 0.0452 and wR = 0.1056 for 17102 independent reflections (Rint = 0.0442) and 11074 observed reflections (I 〉 2σ(I)). Structural analysis indicates that two kinds of octamolybdates ([α-Mo8026]^4- and [β-Mo8026]^4-) co-exist in the compound. This is the first example of a supramolecular structure containing L complex as well as both α- and β-octamolybdate clusters.  相似文献   

14.
1INTRODUCTION More and more chemists have currently been inte-rested in the transition metal oxides(so-called polyoxometalates)mainly owing to their structural varieties and promising potential applications in catalysis,biology,medicine and materials science[1].Of the various polyoxometalate structures,the most interesting one is the molybdate family with a va-riety of structural polymers including{Mo2},{Mo4},{Mo6},{Mo8}.etc.These molybdate polymersmight act as versatile building blocks …  相似文献   

15.
A new cobalt( Ⅱ ) complex [Co(μ-phth)(imi)2]n (phth = o-phthalato, imi = imidazole)has been synthesized by the reaction of CoCl2 with disodium o-phthalate and imidazole. The crystal structure of the compound has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic system, space group Pn with a = 8.405(1), b = 9.995(1), c = 9.996(2) (A),β= 104.479(2),V= 813.0(2) (A)3, Dc= 1.467 g/cm3, C14H12N4O4Co, Mr= 359.21, F(000) = 366,μ = 1.079 mm-1, Z = 2, R = 0.0483 and wR = 0.1209 for 1583 observed reflections (Ⅰ> 2σ(Ⅰ)). In the title complex, the Co(Ⅱ) ions are bridged by o-phthalate ligands in a bidentate mode, producing a zigzag infinite chain structure. Each four-coordinated cobalt( Ⅱ ) center was coordinated by two oxygen atoms and two nitrogen atoms to give a distorted tetrahedral geometry. The chains are linked by hydrogen bonds between oxygen atoms belonging to carboxylate groups and hydrogen atoms of imidazole molecules, forming an unusual two-dimensional coordination polymer.  相似文献   

16.
1 INTRODUCTIONSincethiolateligandwasintroducedintomolybdenumcarbonylcompoundin1 984 [1],theinvestigationonlow valenceMo -SRcompoundshasreceivedattentionforthiskindoflow valencecompoundspossesscertainadvantageoncompoundsyn thesis,moleculestructureandphysicala…  相似文献   

17.
One new polyoxometalate compound connected via nickel/potassium cations, H8K{[Ni(H2O)5]2(H2Mo1.80W10.20O42)}Cl3·16H2O 1, was prepared and characterized by elemental analysis and IR spectroscopy. Single-crystal X-ray diffraction analysis results reveal that clusters of [Ni(H2O)5]2(H2Mo1.80W10.20O42)}6-in compound 1 are linked by potassium cations to form one- dimiensional chains, based on which a three-dimensional network is further constructed via the hydrogen bonds of O…O and O…Cl. Magnetic measurements show that compound 1 has para- magnetic properties. Crystal data: H62Cl3KMo1.80Ni2O68W10.20, Mr = 3461.33, monoclinic, space group C2/c, a = 18.9291(19), b = 16.6758(17), c = 19.1064(19)(A), β = 106.6880(10)(, V = 5777.1(10) (A)3, Z = 4, Dc = 3.980 g/cm3, F(000) = 6250, μ = 21.574 mm(1, R = 0.0579 and wR = 0.1623 (Ⅰ > 2σ(I)).  相似文献   

18.
One novel polyoxometalate compound connected via trivalent cerium cation as bridge H2{[K(H2O)2]2[Ce(H2O)5]2(H2Mo1.16W10.84O42)}·8H2O 1 was designed and synthesized in aqueous solution. X-ray diffraction analysis reveals that the structure of 1 is a three-dimensional framework assembled from the arrangement of H2Mo1.16W10.84O42 (named paradodecmetalate-B) and Ce(H2O)53 containing two planes, which are constructed through the unification of H2Mo1.16W10.84O4210- and Ce(H2O)53 along the [100] and [001] directions. Crystal data: H96Ce4K4Mo2.32O128W21.68, Mr = 7074.89, monoclinic, P21/n, a = 12.5037(17), b = 17.002(2), c = 12.7473(17) (A), β = 105.966(2)°, V = 2605.4(6) (A)3, Z = 1, Dc = 4.509 g/cm3, F(000) = 3132, μ = 26.098 mm(1, R = 0.0377 and wR = 0.0789 (I > 2σ(I)).  相似文献   

19.
Two new polyoxomolybdate compounds,namely CuII2(HL)3]2[Mo8O26]·(H2O)4(1) and [NiII(HL)3]2(Mo8O26)·(H2O)3(2)(HL = 3-(2-pyridyl)pyrazole),were designed and synthesized under hydrothermal conditions.X-ray diffraction analyses reveal that compound 1 consists of one β-Mo8O264-cluster and a Cu2 dimer which is built from two Cu(II) ions linked by three 3-(2-pyridyl)pyrazole ligands.Compound 2 is generated by two kinds of polyoxomolybdate clusters of α-[Mo8O26]4-and β-[Mo8O26]4-.In complexes 1 and 2,the multi-dimensional frameworks are con-structed with the help of hydrogen-bonding links between the terminaloxygen atoms of [Mo8O26]4-,water molecules,and 3-(2-pyridyl)pyrazole ligands.Crystal data of 1:C24H25Cu2Mo4N9O15,Mr = 1190.37,monoclinic,space group P21/c,a = 10.850(2),b = 18.510(4),c = 17.230(3) ,β = 100.57(3)°,V = 3401.6(12) 3,Z = 4,Dc = 2.324 g/cm3,F(000) = 2312,μ = 2.742 mm-1,R = 0.0302 and wR = 0.0775(Ⅰ 2σ(Ⅰ));Crystal data for 2:C48H48Mo8N18Ni2O29,Mr = 2225.98,monoclinic,space group P21/n,a = 20.799(2),b = 14.7970(13),c = 23.141(2) ,β = 91.6180(10)°,V = 7119.0(11) 3,Z = 4,Dc = 2.077 g/cm3,F(000) = 4344,μ = 1.968 mm-1,R = 0.0309 and wR = 0.0696(Ⅰ 2σ(Ⅰ)).  相似文献   

20.
1 INTRODUCTION Polyoxometalates (POMs) have been attracting extensive interest of many chemists in solid-state materials chemistry owning to the various structures and great potential applications in catalysis, medi- cine, photo-electricity and magnetism[1~9]. Over the past decades, lots of novel POMs have been pre- pared by hydrothermal synthesis, such as discrete structure[10], one-dimensional chain-like structure[11, 12] and higher dimensional architecture[13~18]. However, in these…  相似文献   

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