Neptunium(IV) Complex with Carbamide [Np(Urea)8]SiW12O40 · 2Urea · H2O: Synthesis,Crystal Structure,and Properties

The synthesis and crystal structure of [Np(Urea)₈]SiW₁₂O₄₀ · 2Urea · H₂O complex are reported. Crystallographic parameters: space groups C2/c, a = 18.972(5) Å, b = 18.891(5) Å, c = 16.654(4) Å, = 100.847(6)°, Z = 4, V = 5862(3) ų, (calcd) = 4.226 g/cm³. Thermal properties of this compound are studied; absorption spectra in the IR and visible regions are measured.     

Synthesis and Structure of Two Keggin-Type Heteropolyanions: [VMo12O40]3n− n (1) and [H3PMoVMoVI 11O40]1− (2)

Two Keggin-type heteropolyanions were synthesized and characterized by X-ray crystal structure and elemental analysis as well as infrared spectroscopy. Both K₃[VMo₁₂O₄₀]19H₂O (1) and [N _i (H₂O)₆][H₃PMo^VMo^VI ₁₁O₄₀]₂30 H₂O (2) were prepared in aqueous solution. Compound 1 crystallized in the space group Pm-3m, a=10.6513(1) Å, V=1208.4(3) ų, Z=1. Compound 2 crystallized in the space group R-3 with a=b=13.9669(2) Å, c=42.0075(5) Å, V=7096.71(2) ų, Z=3. The compound 1 contains a {K₆VMo₁₂O₄₀} group in which six potassium ions form a regular {K₆} octahedron. The heteropolyanion [VMo₁₂O₄₀]^3– was capped by six potassium ions and enclosed by {K₆} octahedron. A three-dimensional structure was formed by the buildup of {K₃[VMo₁₂O₄₀]} _n . Compound 2 contains a one-electron reduced heteropolyanion [H₃PMo^VMo^VI ₁₁O₄₀]^1–. Ni²⁺ coordinated by six water molecules as the counter cation balances the negative charge of the molecule.     

Hybrid Tungstocuprate [ Cu（2,2＇-bpy）3]2 H4 [ CuW12O40 ]· 6H2O Based on Keggin Polyoxoanion [CuW12O40]^6- with Cu^Ⅱ as Heteroatom

A novel hybrid tungstocuprate （ Ⅱ ） [ Cu （2,2＇-bpy） 3 ] 2 H4 [ CuW12O40 ] · 6H2O （ 2,2＇-bpy = 2,2＇-bipyfidine） was synthesized via hydrothermal method and characterized using elemental analyses, IR, UV, XPS, TG-DSC, EPR, and X-ray single crystal diffraction. The structural analysis shows that the complex consists of an unusual Keggin-type polyoxoanion [ CuW12O40 ]^6- and a pair of chiral complex cations [ Cu（2,2＇-bpy） 3 ]^＋ together with four protons and six crystallization water molecules, and the Keggin polyoxoanion is connected with [ Cu （2,2＇-bpy）3 ]^＋v/a multiple C-H…O hydrogen bonds resulting in a dimer.     

Synthesis,Crystal Structure and Electrochemistry of Two Complexes （YLn）3＋[PW12O40]3-（L=Me2SO,Me2NCHO）

The reaction of α-H3[PW12O40] with Y（NO3）3 in the presence of DMF or DMSO leads to two complexes with the formulae {Y（DMSO）7}·PW12O40（1） and {[Y（DMF）7]2PW12O40}·PW12O40（2）. The crystal structures indicate that complex 1 consists of discrete [YLn]3＋ cations and α-Keggin heteropolyanions [PW12O40]3-, whereas, in complex 2, donor-acceptor interaction results in a cation-anion-cation triplet. In addition, the electrochemical behavior of the two complexes indicates the usual successive reduction processes of the W atoms in the anions.     

Synthesis, Electrochemistry and Crystal Structure of the [Ni36Pt4(CO)45]6− and [Ni37Pt4(CO)46]6− Hexaanions

The [Ni₃₆Pt₄(CO)₄₅]^6- and [Ni₃₇Pt₄(CO)₄₆]^6- clusters have been obtained in mixture upon reaction in acetonitrile of [Ni₆(CO)₁₂]^2- salts with K₂PtCl₄ in a 2.5:1 molar ratio. The two hexaanions were indistinguishable by spectroscopic techniques. Crystallization of their trimethylbenzylammonium salts led to crystals of composition 0.5[NMe₃CH₂Ph]₆[Ni₃₆Pt₄(CO)₄₅]-0.5[NMe₃CH₂Ph]₆[Ni₃₇Pt₄(CO)₄₆]·C₃H₈O, hexagonal,space group P6₃ (No. 173), a=17.853(9), c=27.127(13) Å, Z=2; final R=0.057. The metal core of the [Ni₃₆Pt₄(CO)₄₅]^6- anion consists of a Pt₄ tetrahedron fully encapsulated in a shell of 36 Ni atoms belonging to a very distorted and incomplete ₅ tetrahedron. The [Ni₃₇Pt₄(CO)₄₆]^6- hexaanion derives from the former by capping the unique triangular face of the metal polyhedron with an additional Ni(CO) fragment. The [Ni₃₆Pt₄(CO)₄₅]^6--[Ni₃₇Pt₄(CO)₄₆]^6- mixture is rapidly degraded to the known [Ni₉Pt₃(CO)₂₁]^4- cluster by exposure to carbon monoxide. Its reaction with protic acids initially affords the corresponding [H_6-nNi₃₆Pt₄(CO)₄₅]^n--[H_6-nNi₃₇Pt₄(CO)₄₆]^n- (n=5, 4) derivatives, and eventually leads to rearrangement to the known [H_6-n Ni₃₈Pt₆(CO)₄₈]^n- species. Both [Ni₃₆Pt₄(CO)₄₅]^6--[Ni₃₇Pt₄(CO)₄₆]^6- and [HNi₃₆Pt₄(CO)₄₅]^5--[HNi₃₇Pt₄(CO)₄₆]^5- mixtures have been chemically and electrochemically reduced to their corresponding [Ni₃₆Pt₄(CO)₄₅]^n--[Ni₃₇Pt₄(CO)₄₆]^n- (n=7–9) and [HNi₃₆Pt₄(CO)₄₅]^n--[HNi₃₇Pt₄(CO)₄₆]^n- (n=6–8) mixtures.     

Synthesis and Crystal Structure of the Polyoxometalatebased Complex [Mn（DMSO）5H2O]2SiMo12O40

1 INTRODUCTION The design and assembly of organic-inorganic solid-state materials with active physical properties, such as materials with electrical, magnetic and opti- cal properties, has become a focus of a great deal of interest in recent years[1, 2].…     

Hydrothermal Synthesis, Crystal Structure and Thermal Stability of [Ni(phen)3]·(C8H12O4)·(H2O)14

One novel complex [Ni(phen)3]·(C8H12O4)·(H2O)14 with hexane dicarboxylic acid and 1,10-phenanthroline has been hydrothermally synthesized and characterized. Crystal data: monoclinic, space group C2/c, a = 2.3475(5), b = 1.2208(2), c = 1.9499(4) nm, β = 114.682(3)o, V = 5.0778(16) nm3, Dc = 1.339 g/cm3, Z = 4, μ(MoKα) = 0.458 mm-1, F(000) = 2168, GOOF = 1.014, R = 0.0401 and wR = 0.0961. The nickel(Ⅱ) center in the title complex is coordinated with six nitrogen atoms of three 1,10-phenanthroline molecules, giving a distorted octahedral coordination geometry. However, the nickel(Ⅱ) ion does not coordinate to the hexane dicarboxylic acid. The complex molecules form a 3D structure through hydrogen bonds. TG analysis shows that the title complex is stable below 240.0 ℃.     

Improved Synthesis,Structure, and Solution Characterization of the Cyclic 48-Tungsto-8-Arsenate(V), [H4As8W48O184]36−

We report on an improved synthesis and structural characterization of the cyclic 48-tungsto–8-arsenate(V) [H₄As₈W₄₈O₁₈₄]^36? (1). The mixed lithium–potassium salt of this polyanion, K_26.5Li_9.5[H₄As₈W₄₈O₁₈₄]·90H₂O (KLi-1), has been studied in the solid state by IR, single-crystal X-ray diffraction, and elemental analysis, and in solution by ¹⁸³W NMR spectroscopy.     

Hydrothermal Synthesis,Crystal Structure and Thermal Stability of [Ni（phen）3]-（C8H12O4）-（H2O）14

One novel complex [Ni（phen）3],（C8H12O4）·（H2O）14 with hexane dicarboxylic acid and 1,10-phenanthroline has been hydrothermally synthesized and characterized. Crystal data： monoclinic, space group C2/c, a = 2.3475（5）, b = 1.2208（2）, c = 1.9499（4） nm, β= 114.682（3）°, V = 5.0778（16） nm^3, Dc = 1.339 g/cm^3, Z = 4,μ（MoKa） = 0.458 mm^-1, F（000） = 2168, GOOF = 1.014, R = 0.0401 and wR = 0.0961. The nickel（H） center in the title complex is coordinated with six nitrogen atoms of three 1,10-phenanthroline molecules, giving a distorted octahedral coordination geometry. However, the nickel（Ⅱ） ion does not coordinate to the hexane dicarboxylic acid. The complex molecules form a 3D structure through hydrogen bonds. TG analysis shows that the title complex is stable below 240.0 ℃.     

Studies on the Synthesis and Properties of K_8[TiP_2W_17O_62]·12H_2O

The present paper covers a salt of 2:18 heteropoly complex of tungstotitanophosphate prepared with the method of improved sequence preparation. The title compound was characterized by elemental analysis, 31P NMR spectra, polarography, cyclic voltammetry, IR, UV, X-ray powder diffraction , X-ray photoelectron spectra and TG-DTA analysis. The results show that the complex with the formula K8[TiP2W17O62]·12H2O has Dawson structure. Its properties such as spectra, redox behavior and thermal stability are discussed.     

Hydrothermal Synthesis and Crystal Structure of a Novel Composite Keggin-type Arsenotungstate： [Ni（phen）2] [Hphen] （AsW12O40）

A novel polyoxometalate-based composite compound [Ni(phen)2][Hphen](AsW12O40) (phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and characterized by elemental analysis, IR, TGA, ESR spectroscopy and single-crystal X-ray diffraction. Each structure unit of 1 consists of one polyoxoanion AsW12O403-, one free phenanthroline molecule and one coordination cation [Ni(phen)2]2+. The title compound crystallizes in the orthorhombic system, space group P212121, with a = 12.2383(7), b = 21.0884(11), c = 22.3237(12) , V = 5761.4(5) 3, Mr = 3520.44, Z = 4, Dc = 4.059 g/cm3, F(000) = 6204, μ(MoKα) = 24.844 mm-1, GOF = 1.022, the final R = 0.0376 and wR = 0.0742 (I > 2σ(I)) for 865 parameters and 9637 observed reflections with I > 2σ(I).     

[Bu4N]2[Fe2(μ-S2O3)2(NO)4]: Synthesis,Structure, Redox Properties,and EPR Study

The [n-Bu₄N]₂[Fe₂(-S₂O₃)₂(NO)₄] complex was studied using X-ray diffraction analysis, cyclic voltammetry, and EPR spectroscopy, and its crystal structure was determined. The redox properties of the [Fe₂(-S₂O₃)₂(NO)₄]^2–anion in CH₃CN and CH₂Cl₂solutions were studied. An addition of excess reducer (sodium thiosulfate) to the thiosulfate complex was shown to produce an EPR signal with g= 2.03 typical of the mononuclear iron dinitrosyl complexes. The mechanism for [Fe₂(-S₂O₃)₂(NO)₄]^2–reduction was suggested.     

A High Dimensional Coordination Polymer Based on [β-Mo8O26]4- Inorganic Building Block： Synthesis, Structure and Topology

A high dimensional copper coordination polymer {[Cu2(btb)2(H2O)4( -Mo8O26)] H2O}n(1, btb = 1,4-bis(1,2,4-triazol-1-yl)butane) based on [ -Mo8O26]4 anions and flexible bis(triazole) ligands has been synthesized and characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction and thermal analysis. The crystallographic data show that complex 1 crystallizes in triclinic space group P with a = 9.7550(10), b = 10.3996(11), c = 10.9516(11), = 77.622(2), = 89.602(2), = 87.610(2), V = 1084.25(19)3, C16H34Cu2Mo8 N12O31, Mr = 1785.15, Dc = 2.734 g cm 3, μ(MoKα) = 3.303 mm 1, F(000) = 856, GOF = 1.060, Z = 1, the final R = 0.0376 and wR = 0.0982 for I > 2 (I). In 1, the inorganic building block [ -Mo8O26]4 anions are connected with each other to generate one-dimensional chains. Then the chains are further connected by Cu2+ ions to form a three-dimensional (3D) inorganic framework [Cu2( -Mo8O26)]n containing quadrangular channels, with the pcu alpha-Po primitive cubic topology. The btb ligands are encapsulated into the void of the 3D inorganic framework forming a new three-dimensional architecture. The thermal analysis illustrates that complex 1 retains a comparatively good thermal stability.     

Two new supramolecular compounds based on Ni(II)-Schiff-base and Keggin-type [PMo12O40]3−

Two polyoxometalate-templated nickel-Schiff-base compounds, {[Ni(L)₂]₂[PMo₁₂O₄₀][Cl] · 1.5DMF · H₂O} _n (1) and {[Ni(L)₂]₂[PMo₁₂O₄₀][Cl] · DMSO · CH₃OH · 0.5H₂O} _n (2) (where L is 1,4-bis(4-imidazolyl)-2,3-diaza-1,3-butadiene), were synthesized in situ from Ni²⁺ and L in H₂O/DMF/CH₃OH or H₂O/DMSO/CH₃OH at room temperature and characterized by elemental analysis, infrared spectroscopy, and single-crystal X-ray diffraction analysis. The results of the single-crystal X-ray diffractions suggested that both compounds have the same packing of the Ni(II)-Schiff-base cation layer and Keggin anion layer. Thermogravimetric analyses suggested that two supramolecular compounds have similar thermal stabilities based on the same packing of the cation and anion layers.     

Synthesis,crystal structure and properties of tungstoantimonates with CuII or NiII sandwiched by two [ α -SbW9O33]9− or [ β -SbW9O33]9− subunits

Two sandwich-type tungstoantimonates K₄Na₂H₃[Na₂K(H₂O)₂{Cu(H₂O)}₃(α-SbW₉O₃₃)₂]?·?15H₂O (1) and Na₄H₄[{Ni(H₂O)₃}₂{W(OH)₂}₂{β-SbW₉O₃₃}₂]?·?23H₂O (2) were prepared from aqueous solution by different strategies. They were characterized by X-ray structure analysis, electrochemical analysis, EPR and IR spectroscopy. Both compounds are sandwich-like tungstoantimonates built from two B-[SbW₉O₃₃]^9? building blocks. The polyoxoanion of 1 consists of two trivacant B-α-[SbW₉O₃₃]^9? moieties linked by three Cu²⁺ ions leading to a Hervé-type sandwich framework. The polyoxoanion in 2 is composed of two isomeric B-β-[SbW₉O₃₃]^9? subunits joined together by two Ni²⁺ and two W⁶⁺ ions resulting in a Krebs-type sandwich structure.     

Tailoring Heterometallic Cluster Functional Building Blocks: Synthesis,Separation, Structural and DFT Studies of [Re6−xMoxSe8(CN)6]n−

Influence of the metal core composition and geometry on the structure, spectroscopic properties and redox potentials was investigated for the first time for heterometallic (Re/Mo)₆ octahedral clusters. The discrete anionic clusters [Re_6-xMo_xSe₈(CN)₆]ⁿ⁻ (x=2, 3; n=4, 5) were obtained as individual salts. Their isomeric composition and bond-length distribution were inspected using a combination of single-crystal X-ray structure analysis, NMR, EXAFS, and DFT calculations.