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.

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.

Solid-state Synthesis at Low-heating Temperature and Crystal Structure of a Dinuclear Molybdenum Complex with Oxalate Ligand[Bu_4N]_2[Mo_2O_2(OH)_2Cl_4(C_2O_4)]

The title compound was synthesized by the solid-state reaction of (NH_4)_6Mo_7O_(24)·4H_2O, Na_2C_2O_4, NH_2OH·HCl and Bu_4NBr at 90 ℃ for 10 h and crystallized from acetone-ether. The green crystal belongs to the monoclinic space group P2_1/n with a=9. 908(2), b= 17, 873(2), c= 13/450(2) A , β= 90. 09(1 )°,V = 2381. 6 (7 ) A￣3 , D_c = 1. 359 g/cm￣3 , Z= 2. The structure was refined to R =0. 0427 for 2562 reflections. The anion of the title compound can be described as an oxalate ligand (C_2O4￣2 ) bridging two [MoCl_2O(OH)] units, which contain Mo(V)atoms.

Synthesis and Structure Study of Molybdenum Complex Mo[o-NHCOCH_3-m-NO_2C_6H_3COOH]_2_O2Cl_2·PhCl

The crystal and molecular structures of molybdenum complex, Mo [ o- NHCOCH3- m-NO2C6H3COOH]2O2Cl2.PhCl are reported. The crystal belongs to space group Cc of monoclinic system with unit cell parameters:α= 11. 214 (3) A .b= 19. 544 (4 ) A . c = 14. 091 (6) A .β=94.06(3)°,V'=3080.3 A3 and Z=4. The structure was refined to R=0. 061.The coordination number for the Mo atom Is six. The coordination polyhedron formed by four O atoms and two Cl atoms around the Mo atom is a distorted octahedron. Four O atoms and one Mo atom construct a plane. Two benzyl planes in coordinate groups and the benzyl plane of solvent are almost parallel. The quantum-chemical calculations were carried out. There are hydrogen bonds in the Complex. The EHMO calculations and the existence of hydrogen bonds prove that the O atoms are stronger coordinated atoms in the carbonyls than in the carboxyls.

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.

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.

The Electronic Structures and Chemical Bonding of Some Dinuclear and Trinuclear Low-valence Molybdenum Complexes Containing Thiolate Bridges

The electronic structures of several dinuclears and trinuclears of molybdenum containing thiolates complexes have been calculated by quantum chemistry SCC-DV-Xa method, and the reactivity of complexes has been analyzed in terms of the molecular orbital energy level diagrams, orbital characters and charge populations.

Synthesis and Structure Characterization of Oxo Complex of Molybdenum(Ⅵ): MoO_2(C_9H_6NO)_2

The solid state reaction of MoCl3. 3H2O with 8--hydroxylquinine givesthe title compound MoO2, (C9H6NO)2. The crystallographic data for C18,H12,N2O4.Mo=monoclinic, space group C2/c, a= 13. 357(4), b= 9. 434(2), c= 13. 540(5) A, β=109. 39(6)°, V= 1609 (2) A3, Z= 4, M.= 416. 24, D.= 1. 72 g/cm3, μ(MoKa) 8. 19 cm-l, F(000) = 832, R= 0. 049 and Rw= 0. 058 for 1118 observed refletions.The Mo atom is,coordinated by two N atoms and two O atoms from two 8-hydroxylquinine and other two terminal O atoms, forming octahedral coordination geometry.

THE FIRST BINUCLEAR MOLYBDENUM AND TUNGSTEN COMPLEXES WITH DOUBLY-BRIDGING PYRIDINE-2-THIOLATO LIGANDS.X-RAY CRYSTAL STRUCTURE OF THE COMPLEX[Mo_2(CO)_4(μ-pyS)_2(PPh_3)_2].2C_7H_8

The title complex was obtained by reactions of [Mo(CO)_3(MeCN)_3] with [CuBr(pySH)(PPh_3)_2]or directly with pySH and PPh_3. The latter method can be used to synthesize the corresponding tungsten complex [W_2(CO)_4(μ-pyS)_2(PPh_3)_2].The molecular structure of the title compound was determined by X-ray diffraction method.

SYNTHESIS AND STRUCTURE OF A MIXED-VALENCE HEXAMOLYBDENUM COMPLEX [Et_4N]_2[Mo_6O_(19)H_4]

A hexamolybdenum complex, [Et_4N]_2[Mo_6O_(19)H_4] crystal, with pentavalent and hexavalent molybdenum has been obtained in the solution of DMF and CH_3OH as organic solvents using MoCl_5 as a starting material. The crystallographic parameters obtained by X-ray diffraction analysis are: crthorhombic, a=10. 757(3), b=10. 763(2), c=14. 238(4)A, =1648. 9A^3; Z=2; space group Pnnm; final R=0. 047; final Rw=0. 051^(**)

Catalytic epoxidation of olefin over supramolecular compounds of molybdenum oxide clusters and a copper complex

The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu（bipy）]4[Mo15O47].2H2O （1） and [Cu1（bix）][（Cu1bix） （δ-MoVl8O26）0.5] （2） （bipy = 4,4＇-bipyridine, bix = 1,4-bis（imidazole-1-ylmethyl）benzene）. Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide （t-BuOOH） as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.

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.

Synthesis and Crystal Structure of Cubane-type Molybdenum Cluster Complex Mo_4S_4(DTP)_4[μ-SOP(OEt)_2]_2

A cubane-type molybdenum cluster compound Mo4S4(DTP)4[-SOP(OEt)2]2 A (DTP = diethyl dithiophosphate) was obtained from the reaction of cation [Mo3O2S2(H2O)9]4+ B with metal tin as well as HDTP. The crystal structure has been determined by X-ray crystallography and the data for the title compound: Mo4S14P6O14C24H60, triclinic P , Mr = 1591.14, a = 12.5596(5), b = 14.3441(5), c = 18.0005(6) ? = 85.318(1), = 70.495(1), = 78.415(2)? V = 2994.2(2) ?, Z = 2, Dc = 1.765 g/cm3, (MoK? = 1.515 mm-1, F(000) = 1596, R = 0.0918 and wR = 0.1908 for 3546 reflections (I > 2(I)). X-ray analysis reveals that two weak CH贩稯 hydrogen bonds exist in the packing diagram with C贩稯 distance 3.22(5) ? The structure of A is similar to that of -Mo4S4(DTP)6 except that one sulfur of each bridging DTPs has been replaced by oxygen during the reaction, resulting in two bridging [SOP(OEt2)2] - ligands.

Complexation of Molybdenum (Ⅵ) with R-and S-malic Acid, The Crystal Structure of (NH_4)_4[(MoO_2)_4O_3(R-mal)_2]·6H_2O

Ammonium tetramolybdate ( NH4 )4[(MoO2)4O3 (R-mal)2]·6H2O(mal= malic acid)and (NH4)4[(MoO2)4O3(S-mal)2)·6H2O have been prepared by the reaction of R and S-malic acid with ammonium heptamolybdate, respectively. The two complexes are enantiomeric and isomorphous. The complex of Risomer crystallizes in monoclinic space group C2 with unit cell parameters:a = 14. 591 (2 ), b = 10. 108(2), c=11. 464(2), β=121. 48(1)°, V=1441. 9(4),Z=2, Fω=1002. 13, Dc=2. 308, Dm=2. 3 g/cm3. F(000) = 988, MoKα radiation (λ=0. 71073 ), μ (MoKα) = 17. 7 cm-1. Final R=0. 027 for 1491 reflections with I>2. 5 σ(I). Analysis of molecular structure reveals that the complex anion contains a (Mo2O5)O(Mo2O5)core with the bridging oxo-group passing through two-fold axis. Each molybdenum is hexacoordinated , and the malate ligand is quadridentated to two molybdenum atoms by the deprotonated hydroxy-, α- and β-carboxylate groups. Principal dimensions are:[Mo=O(t)]av, 1. 705(6); [Mo-O(b)]av, 1. 920(6); Mo-O(hydroxy). 1. 925(6);Mo-O(α-carboxy), 2. 226 (6), and [Mo-O(β-carboxy)av, 2. 296 (5).Lattice water is distributed throughout the cell and together with various types of the anion oxygens, making H-bonding.

Electrical structure identification of deep shale gas reservoir in complex structural area using wide field electromagnetic method

To fully exploit the technical advantages of the large-depth and high-precision artificial source electromagnetic method in the complex structure area of southern Sichuan and compensate for the shortcomings of the conventional electromagnetic method in exploration depth,precision,and accuracy,the large-depth and high-precision wide field electromagnetic method is applied to the complex structure test area of the Luochang syncline and Yuhe nose anticline in the southern Sichuan.The advantages of the wide field electromagnetic method in detecting deep,low-resistivity thin layers are demonstrated.First,on the basis of the analysis of physical property data,a geological–geoelectric model is established in the test area,and the wide field electromagnetic method is numerically simulated to analyze and evaluate the response characteristics of deep thin shale gas layers on wide field electromagnetic curves.Second,a wide field electromagnetic test is conducted in the complex structure area of southern Sichuan.After data processing and inversion imaging,apparent resistivity logging data are used for calibration to develop an apparent resistivity interpretation model suitable for the test area.On the basis of the results,the characteristics of the electrical structure change in the shallow longitudinal formation of 6 km are implemented,and the transverse electrical distribution characteristics of the deep shale gas layer are delineated.In the prediction area near the well,the subsequent data verification shows that the apparent resistivity obtained using the inversion of the wide field electromagnetic method is consistent with the trend of apparent resistivity revealed by logging,which proves that this method can effectively identify the weak response characteristics of deep shale gas formations in complex structural areas.This experiment,it is shown shows that the wide field electromagnetic method with a large depth and high precision can effectively characterize the electrical characteristics of deep,low-resistivity thin layers in complex structural areas,and a new set of low-cost evaluation technologies for shale gas target layers based on the wide field electromagnetic method is explored.

Discussion on the Complex Structure of Nilpotent Lie Groups Gk

Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent Lie group Gk, defined by the nilpotent Lie algebra g/ak, where g is the Lie algebra of G, and ak is an ideal of g. Then, J gives rise to an almost complex structure Jk on Gk. The main conclusion obtained is as follows: if the almost complex structure J of a nilpotent Lie group G is nilpotent, then J can give rise to a left-invariant integrable almost complex structure Jk on the nilpotent Lie group Gk, and Jk is also nilpotent.

Electrochemical and Spectroelectrochemical Studies of Molybdenum and Neodymium Complex with Diethyld

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Input Structure Design for Structural Controllability of Complex Networks

This paper addresses the problem of the input design of large-scale complex networks.Two types of network components,redundant inaccessible strongly connected component(RISCC)and intermittent inaccessible strongly connected component(IISCC)are defined,and a subnetwork called a driver network is developed.Based on these,an efficient method is proposed to find the minimum number of controlled nodes to achieve structural complete controllability of a network,in the case that each input can act on multiple state nodes.The range of the number of input nodes to achieve minimal control,and the configuration method(the connection between the input nodes and the controlled nodes)are presented.All possible input solutions can be obtained by this method.Moreover,we give an example and some experiments on real-world networks to illustrate the effectiveness of the method.

Generalized response displacement methods for seismic analysis of underground structures with complex cross section

The response displacement method(RDM)is recommended for the seismic analysis of underground structures in the transverse direction for many codes,including bases for design of structures-seismic actions for designing geotechnical works(ISO 23469)and code for seismic design of urban rail transit structures(GB 50909-2014).However,there are some obvious limitations in the application of RDM.Springs and the shear stress of the soil could be approximately evaluated for the structures having a simple cross section,such as rectangular and circular structures.It is necessary to propose simplified seismic analysis methods for structures with complex cross sections.This paper refers to the idea of RDM and proposes three generalized response displacement methods(GRDM).In GRDM1,a part of the soil surrounding a structure is selected to generate a generalized underground structure with a rectangular cross section,and the same analysis model as RDM is applied to analyze the responses of the structure.In GRDM2,a hollow soil model without a generalized structure is used to compute the equivalent load caused by the relative displacement of the soil,and the soil-structure interaction model is applied to calculate the responses of the structure.In GRDM3,a continuous soil model is applied to compute the equivalent load caused by the relative displacement and shear stress of the soil,and the soil-structure interaction model is applied to analyze the responses of the structure,which is the same as the model used in GRDM2.The time-history analysis method(THAM)is used to evaluate the accuracy of the proposed simplified methods.Results show that the error of GRDM1 is about 20%,while the error is only 5%for GRDM2 and GRDM3.Among the three proposed methods,GRDM3 has obvious advantages regarding calculation efficiency and accuracy.Therefore,it is recommended to use GRDM3 for the seismic response analysis of underground structures that have conventional simple or complex cross sections.

Probing electronic structures of transition metal complexes using electron paramagnetic resonance spectroscopy

Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work.