Synthesis and Crystal Structure of Binuclear Oxomolybdenum(VI) Complex with Both o-Mercaptophenolate

The complex (Bu4N) 2 [Mo2O5 (mp)2] was synthesized by the reactionof (Bu4N)2[Mo8O26] with H2mp (H2mp=o-mercaptophenol) in methanol. The molecular formula is C44H80Mo2N2O7S2, M.=1005.10. The complex is crystallized in monoclinic, space group P21/n with unit cell parameters, a = 17. 829 (2) A, b= 13. 759 (2 )A,c= 21. 974(2) A, g=105. 386(8)°, V= 5197. 4(1) , Dc= 1. 285 g/cm3, Z=4,λ(MoKa) =0. 71073 , μ=0. 607 mm-1,F(000) = 2120, final R=0.0348 and wR=0. 0741 for 4912 independent observed reflections (FM>4σ(Fo) ). Two MoO5S units inthe complex molecule exhibits the con facial distorted bioctahedral geometry and possesses an approximate C2 symmetry.

Synthesis and Crystal Structure of a Molybdenum Carbonyl Compound with Thiolate and Dithiocarbamate Ligands, [Bu_4N][(OC)_4Mo(μ-SC_6H_5)_2Mo(C_5H_(10)CNS_2)(CO)_2]

A di-molybdenum carbonyl compound containing thiolate and dithiocarbamate ligands, [Bu4N][（CO）4Mo（μ-SC6H5）2Mo（C5H10dtc）（CO）2] 1 （CsH10dtc = S2CNC5H10）, has been prepared by reaction of [Mo2（SC6H5）2（CO）8] with C5H10dtcNa and [NBu4]Br in acetone. It crystallizes in monoclinic, space group P21/n with a = 13.162（3）, b = 17.466（2）, c = 20.453（4） A,β= 100.77（1）°, Z = 4, V= 4619（2）A^3, C40H56Mo2N2O6S4, Mr = 980.95, De= 1.389 g/cm^3,μ = 7.66 cm^-1, F（000） = 1988 and R = 0.0746 for 5161 observed reflections with I 〉 2σ（I）. The complex contains a [Mo2S2]^2- planar core in which one Mo atom is chelated by a C5H10dtc ligand, leading to different coordination environments of the two Mo atoms. 95Mo NMR measurement indicates that the two Mo atoms are in different oxidation states.

Synthesis and Crystal Structure of a New Dimolybdenum(V) Complex Na_4[Mo_2O_4(HNTA)_2]_2·19H_2O

The new binuclear molybdenum（V） complex Na4[Mo2O4（HNTA）2]2·19H2O （NTA = nitrilotriacetate） has been prepared and characterized by single-crystal X-ray diffraction analysis and IR. The crystal has space group Pnma with a = 10.2239（2）,b = 23.8174（3）,c = 23.1845（4） A,V = 5645.58（16）A^3,Z = 4,C24H66Mo4N4Na4O51,Mr = 1702.50,Dc = 1.958 g/cm^3,μ = 1.027 mm^-1,F（000） = 3280,T = 293（2） K,the final R = 0.0609 and wR = 0.1449 for 5512 observed reflections （I 〉 2σ（I））. Each MoV atom has a distorted octahedral coordination geometry,and the two coordination octahedra share a common edge to form a dioxo-bridged Mo2O4 unit which is coordinated by NTA ligands. The dianionic binuclear units [Mo2O4（HNTA）2]^2- are interconnected by Na^＋ into a layered structure.

MOLECULAR AND CRYSTAL STRUCTURES OF TETRANUCLEAR MOLYBDENUM CLUSTER[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)~6]■

The new cluster[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)_6]has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid.The crystal and molecular structures were determined by the X-ray diffraction method.It crystallizes in the orthorhombic space group Pnna with cell parameters:Mr=1361.6,a=13.792(4), b=17.957(3),c=20.974(9) ,V=5194(2) ~3,Z=4,Dc=1.74/cm^3,F(OOO)=2704,μ(MoK ) =11.0/cm,R=0.074.

Synthesis and Crystal Structure of cis-Bis(3-hydroxy2-ethyl-4-pyranonato)dioxomolybdenum(Ⅵ)

The complex MoO2(C7H7O3)2 has been prepared by the reaction of 3-hydroxy- 2-ethyl-4-pyranone with (NH4)6Mo7O244H2O. The single-crystal X-ray study shows that the coordination sphere about the molybdenum atom in the complex consists of six oxygen atoms arranged in a distorted octahedral geometry with the dioxo ligands in cis positions. The crystal is of monoclinic, space group P21/c with a = 8.3968(2), b = 12.7534(4), c = 14.5443(4) ? b = 96.277(1), V = 1548.18(7) ?, Z = 4, C14H14O8Mo, Mr = 406.19, Dc = 1.743g/cm3, m = 0.886mm-1, F(000) = 816, R = 0.0444 and wR = 0.1091 for 2336 observed reflections with I>2s(I). The average Mo=O bond length is 1.695(4) ? The two ketonic oxygen atoms of the pyranone moieties are trans to the oxo ligands and the hydroxy oxygen atoms are trans to each other. The average MoO bond lengths are 2.248(4) ?for the ketone oxygens and 2.005(3) ?for the hydroxy oxygens. The average ligand bite angle of OMoO is 75.2(2) and the bond angle between two Mo=O is 105.1(2). The dihedral angle is 79.16(2)?between two chelate ring planes.

Syntheses, Crystal Structures and NMR of Two Molybdenum Complexes with 2,3-Dihydroxynaphthalene

Two complexes [H3N（CH2）2NH2]2[MoO2（C10H8O2）2] （1） and （C7H10N2）2- [MoO2（C10H8O2）2] （2） were obtained at nearly the same reaction condition and characterized by IR, 1H and 13C NMR and single-crystal X-ray diffraction. Both of the complexes possess complex anion [MoO2（C10H8O2）2]2- which shows a pseudo-octahedrally coordinated fashion. In complex 1, ethyldiamine presents just as a cation. However, in complex 2, ethyldiamine combines with the acetyl acetone as a byproduct which is confirmed by NMR.

Hydrothermal Synthesis and Crystal Structure of a New Sandwich-type Molybdenum Phosphate

The crystal structure of the title compound, [enH2][Fe{MoⅤ6O12(OH)3(HPO4)- (H2PO4)3}2]6en6H2O (en = H2NCH2CH2NH2), hydrothermally synthesized from a mixture of Na2MoO42H2O, Fe2(SO4)3, H3PO4, H2N(CH2)2NH2 and water, has been determined by single- crystal X-ray diffraction. The crystal is of triclinic, space group P?with a = 11.9014(1), b = 13.4246(2), c = 13.8719(2) , a = 87.465(1), b = 69.981(1), g = 64.960(1)? V = 1873.46(4) 3, Z = 1, Mr = 2997.89, F(000) = 1466, m = 2.427 mm-1 and Dc = 2.657 g/cm3. The final R = 0.0404 for 5570 observed reflections (I > 2s(I)). The structural analysis reveals that each cluster anion contains two coplanar {Mo6} rings of six edge-sharing Mo(O5OH) octahedra, and the two {Mo6} rings are linked together through one octahedral FeⅡ ion to generate a sandwich-type cluster with rigorous () symmetry. Moreover, these clusters are further linked into a three-dimensional frame- work by hydrogen bonds.

碳化钼的结构、制备及应用研究进展

将碳原子引入钼的晶格中形成碳化钼时,形成的间充结构具有独特的物理和化学性质,在加氢反应和制氢反应等领域具有优异的催化性能,可与贵金属铂、钯相媲美。碳化钼化学性质活泼,合成方法和实验条件都密切影响着最终产品的物化性质,任何一种反应原料和实验条件发生微小变化,都可能造成碳化钼的晶相结构、晶粒大小、比表面积等产生较大变化,从而改变材料的催化性质。本文对几种典型碳化钼的晶相类型及空间结构分别进行了介绍,分析了影响碳化钼结构的电子性质和几何因素,系统总结了碳化钼的合成策略并指出了不同制备方法的优劣势。以程序升温还原法为例,分析了碳化钼的生长机理,并从碳化终温、升温速率、碳源浓度三方面着重讨论了制备条件对材料的影响。然后总结了碳化钼在加氢反应、制氢反应、传感器及生物医学材料等领域的应用,详细阐述了碳化钼在电催化析氢和CO_(2)加氢转化反应中的催化机理及改进策略,最后基于目前存在的挑战进一步提出碳化钼材料未来的发展方向。

钨钼分离方法的研究进展

概述了几种常用的钨钼分离方法,包括沉淀分离法、萃取分离法、结晶分离法和吸附分离法等,通过对比反应条件和除钨效率,分析了4种分离方法的优劣,并提出了未来的研究与开发建议。

Synthesis and Crystal Structure of an Incomplete Cubane-type Mo_3S_4 Cluster with the N-N-O Type Tridentate Ligand: {Mo_3S_4[NH_2CH_2CH(O)CH_2NH_2]_3}(DTP)·(H_2O)_2·(DMF)

A new cluster {Mo3S4[NH2CH2CH(O)CH2NH2]3}(DTP)?(H2O)2?(DMF) (DTP = diethyldithiophosphate) has been synthesized via ligand substitution reaction of Mo3S4(DTP)4(H2O) with an alkaline ligand 1,3-diamino-2-propanol(DAPROH) in a mixed organic solvent, and its crys- tal structure was determined with the following data: Mo3S6PC16H48O8N7, Mr = 977.76, triclinic, space group P1, Z = 2, a = 10.319(2), b = 12.843(3), c = 15.335(3) ?, α = 65.26(3), β = 82.18(3), γ = 70.67(3)o, V = 1741.7(6) ?3, Dc = 1.864 g/cm3, μ = 1.517 mm-1, F(000) = 988, the final R = 0.0794 and wR = 0.2111 for 6318 observed reflections (I>2σ(I)). The structure analysis indicates that all DTP ligands of Mo3S4(DTP)4(H2O) are replaced and each DAPRO molecule acts as a tri- dentate ligand chelating to each Mo atom of the Mo3S4 core. Different from the precursor, the clus- ter symmetry is elevated to C3. In addition, the UV-spectrum of the title compound was measured.

Synthesis and Crystal Structure of [MoOS_3Cu_3I(dmpzm)_2]·2(MeCN)_(0.5) (dmpzm=Bis(3,5-dimethylpyrazolyl)methane)

Reaction of a preformed cluster [Et4N]4[Mo2O2S6Cu6I6] with bis（3,5-dimethylpyrazolyl）methane （dmpzm） in acetonitrile afforded the title compound [MoOS3Cu3I（dmpzm）2]·2（MeCN）0.5 1. The single-crystal X-ray diffraction study shows that 1 （C24H35Cu3IMoN9OS3, Mr = 975.25） crystallizes in triclinic, space group P1^- with a = 11.442（2）, b = 11.644（2）, c = 16.211（3） A, α = 99.26（3）, β= 102.22（3）, γ = 118.51（3）°, V = 1766.5（10） A^3, Z = 2, Dc = 1.834 g/cm^3, T = 193（2） K, F（000） = 960, μ = 32.12 cm^-1, λ = 0.71073A^3, R = 0.0355 and wR = 0.0915 for 5686 observed reflections with Ⅰ 〉 2σ（Ⅰ）. In the molecular structure of 1, the [MoOS3]^2- anion acts as a tridentate ligand to bind one CuI group and two [Cu（dmpzm）]^＋ units to form a nido-like [MoOS3Cu3] core with an approximate C2v symmetry. The Mo…Cu contacts are in the range of 2.6460（12）～2.6798（11）A.

Synthesis and Crystal Structure of a Mo-S Cluster Compound Coordinated by Isonicotinate

A cluster compound, Mo3S4（DTP）3（IN）（Py）·EtOH I （DTP = diethyl dithiophosphate, IN = isonicotinate） has been rationally synthesized and characterized by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 13.6345（2）, b = 13.7805（2）, c = 14.5400（1）A, α = 107.078（1）, β = 113.380（1）, γ = 96.310（1）°, C25H45Mo3- N2O9P3S10, Mr = 1218.96, V = 2315.75（5） A^3, Z = 2, Dc = 1.748 g/cm^3, μ = 1.399, F（000） = 1224, R = 0.0425 and wR = 0.1144 for 6335 observed reflections （I 〉 2σ（I））. 31^P NMR spectrum has been measured with the resonance 110.050 and 108.783 （2：1）.

Influence of Deposition Conditions on the Crystal Structure of MoS_2 Coating

MoS2 coatings were prepared using an unbalanced bipolar pulsed DC （direct current） magnetron sputtering apparatus under different targets, cathode current densities, power modes and bias voltages. The morphology, structure and growth characteristics of MoS2 coatings were observed and identified respectively by scanning electron microscopy, X-ray diffractometry and mass spectrometry. The results show that MoS2 coatings evolve with the （002） basal plane parallel to the surface by using cold pressed target with lower density, lower cathodic current density, bipolar pulse DC power and minus bias voltage, whereas the coatings deposited under hot pressed target, higher cathodic current density, simple DC power and positive bias voltage have the （002） basal plane perpendicular to the surface. The influence of deposition conditions on the crystal structure of MoS2 coating is implemented by altering its growth rate and the energy of sputtering-deposition particles.

FORMATION OF MOLYBDENUM OXIDE NANOSTRUCTURES CONTROLLED BY POLY(ETHYLENE OXIDE)

Polymeric systems have played an important role as structure-directing agents and in the control of nucleation and growth of crystals.This article reviews the work of our research group in the field of the polymer-assisted crystallization of inorganic materials,mainly focused on the formation of highly ordered,porous molybdenum oxide nanostructures.Different experimental parameters including the influence of poly(ethylene oxide)-containing polymers on the morphology and structure of the products obtained fr...

Hydrothermal Syntheses, Structure Characteristics and Magnetic Properties of a Series of New Molybdenum Arsenates Based on {(As3O3)2(Mo6O18)(MO6)}(M = Ni, (1); Co, (2); Zn, (3))

Three new polyoxometalates K2[H2（As3O3）2（Mo6O18）（NiO6）]？H2O （1）, K2[H2-（As3O3）2（Mo6O18）（CoO6）]？H2O （2） and [Zn（H4,4？-bpy）2（H2O）4][（As3O3）2（Mo6O18）（ZnO6）]？4H2O （3） （4,4？-bpy = 4,4？-bipyridine） have been synthesized under hydrothermal conditions and characterized by IR, elemental analyses, XPS and single-crystal X-ray diffraction analyses, respectively. Compound 1 represents a new 3D framework structure constructed from polyoxoanion [（As3O3）2（Mo6O18）（NiO6）]4- via covalent bond. Compound 2 has an identical structure with 1. Compound 3 represents a new 2D layer structure constructed from transition metal coordination cations [Zn（H4,4？-bipy）2（H2O）4]4＋, lattice water molecules and polyoxoanions [（As3O3）2- （Mo6O18）（ZnO6）]4- via multi-point N–H？？？O and O–H？？？O hydrogen bonding interactions. Crystal data： for 1, cubic, space group Pa-3, a = 15.0022（8） ？, V = 3376.5（3） ？3, Z = 24; for 2, cubic space group Pa-3, a = 15.1596（10）, V = 3483.88 ？3, Z = 24; for 3, monoclinic, space group C2/m, a = 19.699（4）, b = 14.223（3）, c = 9.1455（18） ？, β = 106.80（3）o, V = 2453.0（9） ？3, Z = 8. In addition, the magnetic behaviors for compounds 1 and 2 have been investigated.

Synthesis and Crystal Structure of an Incomplete Cubane-like Heterobimetallic Cluster [（η^5-C5Me5）2Mo2（μ3-S）（μ-S）3（CuCl）]

The reaction of[（η^5-C5Me5）2Mo2（μ3-S）（μ-S）3（CuCl）]1 with Na2S in MeCN produced a trinuclear cluster [（η^5-C5Me5）2Mo2（μ3-S）（μ-S）3（CuCl）] 2. 2 crystallizes in the monoclinic system, space group P21/c with a = 15.563（3）, b = 8.9547（18）, c = 17.846（4） A, β = 101.29（3）°, V = 2438.9（9） A^3, Z = 4, Dc = 1.878 g/cm^3, T = 193（2） K, C20H30ClCuMo2S4, Mr = 689.60, F（000） = 1376, μ（MoKa） = 2.335 mm ^-1, S = 1.050, R = 0.0305 and wR = 0.0688 for 4033 observed reflections with I 〉 20-（I）. In the structure of 2, one [（η^5-C5Me5）2Mo2（μ-S）2S] moiety and one CuCI unit are assembled into an incomplete cubane-like [Mo2S4Cu] core framework, in which the Cu center adopts a distorted tetrahedral geometry coordinated by one ,μ3-S atom, two μ-S atoms and one terminal chloride. The two Mo…Cu contacts are 2.7519（7） and 2.7689（8） A, respectively.

Structure of Molybdenum Complex of Benzothiazole-2-thiolate（η￣5-C5H5）Mo（CO）2（C7H4NS2）

C14H9NO2S2Mo,Mr=383.29,triclinic,space group P1,a=11.658（4）,b=16.218（8）,c=7.895（3）,a=97.58（4）,β=106.04（3）,γ=85.62（3）°,V=1421（2）,Z=4,Dc=1.79 g/cm￣3,μ=11.81 cm￣（-1）.F（000）=760.Refinement converged to R=0.049 and Rω=0.058 for 3153 independent observed reflections.The compound is a mononuclear molybdenum complex containing benzothiazole-2-thiolato ligand.The molybdenum atom is coordinated by the two carbonyl carbon atoms,tlie cyclopentadienyl carbon atoms,and the nitrogen atom and sulfur atom of benzothiazole-2-thiolate.The coordination polyhedron may be described as a trapezoidal pyramid with the Cp ring centroid as a top.

Synthesis and Crystal Structure of a New Mixed-ligand Cluster[Mo_3O_4(C_2O_4)_2bipy(H_2O)_3]·EtOH·2H_2O(bipy = 2,2'-Bipyridine)

The novel mixed-ligand neutral compound [Mo3O4（C2O4）2bipy-（H2O）3]·EtOH·2H2O（bipy = 2,2′-bipyridine） has been prepared by the reaction of oxalic acid elution of Mo（IV） and bipy, and characterized by single-crystal X-ray diffraction analysis and IR. The crystal is of triclinic, space groups P1^- with a = 9.5520（2）, b = 10.3730（1）, c = 13.5722（2）A, a = 74.940（12）,β = 80.772（14）,γ= 69.898（11）°, V = 1215.73（11）A^3, Z = 2, C16H24Mo3N2O18, Mr = 820.19, Dc = 2.241 g/cm^3,μ = 1.616 mm^-1, F（000） = 808, T = 293（2） K, the final R = 0.0424 and wR = 0.0939 for 4119 observed reflections with I 〉 2σ（I）. The trinuclear unit is coordinated by mixed ligands of oxalate and bipy. The intermolecular hydrogen bonding interactions among adjacent [Mo3O4（C2O4）2·bipy（H2O）3] extend the compound into a three-dimensional supramolecular framework. The uncoordinated water molecules and ethal molecules act as space-fillers and consolidate the whole architecture through hydrogen bonding interactions.

Hydrothermal Synthesis and Structure of a Novel Binuclear Molybdenum Complex with Oxalate Ligand, (enH_2){NH_4[Co(en)_3][Mo_2O_7(C_2O_4)] }_2·2H_2O

The title complex (enH2){NH4[Co(en)3][Mo2O7(C2O4)]}22H2O (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) ? b = 103.878(7), V = 2274.8(2) 3, Dc = 2.039 g/cm3, Z = 2, m(MoKa) = 1.878 mm-1 and F(000) = 1408. The final R = 0.0410 and wR = 0.1070 for 4065 observed reflections with I≥2s(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.

Hydrothermal Synthesis,Crystal Structure and Fluorescent Property of a Novel Mo(V) Phosphate [Zn(Mo^v_6P_4O_(31)H_(10))_2(C_4H_(14)N_3)_2]·2C_4H_(13)N_3·8H_2O

A new molybdenum phosphate [Zn（Mo^v6P4O31H10）2（C4H144N3）2].2C4H13N3.8H2O 1 （C4H13N3 = diethylenetriamine） has been synthesized under hydrothermal condition. Single-crystal X-ray diffraction reveals that compound 1 crystallizes in the monoclinic, space group P21/n, a = 13.1679（3）, b = 22.1240（6）, c = 13.6146（3） A, β= 103.4847（7）°, V = 3856.95（16） A^3, C16H90N12O70P8ZnMo12, Mr = 3035.41, Z = 2, Dc = 2.614 g/cm^3, μ = 2.483 mm^-1, F（000） = 2968, S = 1.014, the final R = 0.0196 and wR = 0.0506 for 7486 observed reflections （1 〉 2σ（I））. Compound 1 consists of two identical rings of six edge-sharing MoOt, octahedra interconnected by one ZnO6 octahedron, whereas the PO4 tetrahedra which share their apices with the MoO6, octahedra are only located on one side of each Mo6, ring. The 2-charge of polyanion [Zn（Mo^v6P4O31H10）2]^2- unit is compensated in the crystal by two mono-protonated diethylenetriamines （C4H14N3）^＋. By hydrogen bonding interactions the polyanion of compound 1 is interconnected to form pseudo threedimensional molybdophosphate. Other characterizations by elemental analyses, IR spectrum and fluorescent spectrum are also described.