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1.
由贫硫化合物{Mo_3S_4[S_2P(OEt)_2]_4·H_2O}通过加硫获得了富硫化合物{Mo_3S_7[S_2P(OEt)_2]_3·I}(CH_8C_6H_5).化合物属三斜晶系,空间群PI,晶胞参数为a=10.350(1)A,b=13.931(4)A,c=16.369(3)A,α=103.69(2),β=86.62(1),γ=111.99(2)°,V=2183A~3;z=2,D_c=1.817g·cm~(-3).最终结构偏离因子R为0.042. 簇分子{Mo_3(μ_3-S)(μ-S_2)_3[S_2P(OEt)_2]3·I}属{Mo_3(μ3一Y)(μ-S_2)_3[S_2P(OEt)_2]_3·X}(Y=O,S;X=Cl,I)系列构型.{Mo_3}基本上是一个正三角形,Mo—Mo键长分别为2.721(1),2.724(1),2.725(1)A,Mo的配位多面体为七个硫原子组成的畸变五角双锥,有一个I原子联结着三个(S_2)~(2-)桥基的三个不与Mo共平面的S原子,I—S距离平均为3.169A,比相应的Van der Waals距离(~4.00A)明显地短,显示一定程度的成键作用,簇分子的这一构型是一种较为稳定的结构类型.  相似文献   

2.
Quantum chemical calculations at the DFT level have been carried out for model complexes [Mo(P)(NH2)3] (1), [Mo(N)(NH2)3] (2), [Mo(PO)(NH2)3] (3), [Mo(NO)(NH2)3] (4), [Mo(CO)5(PO)]+ (5), and [Mo(CO)5(NO)]+ (6). The equilibrium geometries and the vibration frequencies are in good agreement with experimental and previous theoretical results. The nature of the Mo–PO, Mo–NO, Mo–PO+, Mo–NO+, Mo–P, and Mo–N bond has been investigated by means of the AIM, NBO and EDA methods. The NBO and EDA data complement each other in the interpretation of the interatomic interactions while the numerical AIM results must be interpreted with caution. The terminal Mo–P and Mo–N bonds in 1 and 2 are clearly electron-sharing triple bonds. The terminal Mo–PO and Mo–NO bonds in 3 and 4 have also three bonding contributions from a σ and a degenerate π orbital where the σ components are more polarized toward the ligand end and the π orbitals are more polarized toward the metal end than in 1 and 2. The EDA calculations show that the π bonding contributions to the Mo–PO and Mo–NO bonds in 3 and 4 are much more important than the σ contributions while σ and π bonding have nearly equal strength in the terminal Mo–P and Mo–N bonds in 1 and 2. The total (NH2)3Mo–PO binding interactions are stronger than for (NH2)3Mo–P which is in agreement with the shorter Mo–PO bond. The calculated bond orders suggest that there are only (NH2)3Mo–PO and (NH2)3Mo–NO double bonds which comes from the larger polarization of the σ and π contributions but a closer inspection of the bonding shows that these bonds should also be considered as electron-sharing triple bonds. The bonding situation in the positively charged complexes [(CO)5Mo–(PO)]+ and [(CO)5Mo–(NO)]+ is best described in terms of (CO)5Mo → XO+ donation and (CO)5Mo ← XO+ backdonation (X = P, N) using the Dewar–Chatt–Duncanson model. The latter bonds are stronger and have a larger π character than the Mo-CO bonds.  相似文献   

3.
We report the electrochemical and chemical synthesis of the first isolable iron carbonyls obtained directly from an {Fe4S4}-cluster and carbon monoxide: the structure of one product of chemical reduction, [Fe3S(CO)9]2−, had been determined by X-ray crystallography.  相似文献   

4.
The new Mo/Se clusters [Mo33-Se)(μ2-Se2)3{N(SePPh2)2}3]Br (1) and [Mo33-Se)(μ2-Se2)3{Se2P(OCH2CH3)2}3]Br (2) have been synthesized by the selective substitution of the bromo ligands in the starting material [PPh4]2[Mo33-Se)(μ2-Se2)3Br6] with the selenoorgano bidentate ligands [N(SePPh2)2] and [Se2P(OEt)2]. The complexes have been characterized in solution by 31P- and 77Se-NMR spectroscopy and in the solid state by single crystal X-ray diffraction; the same cation structures are present both in solution and in the solid state. Crystallographic data for 1: [Mo33-Se)(μ2-Se2)3{N(SePPh2)2}3]Br·3 CH2Cl2, C72H60BrMo3N3P6Se13·3 CH2Cl2, trigonal, space group R3, a=21.299 (10) Å, c=38.433 (27) Å, V=15 100 (15) Å3, T=−120 °C, Z=6; crystallographic data for 2: Mo33-Se)(μ2-Se2)3{Se2P(OCH2CH3)2}3]Br, C12H30BrMo3P3O3Se13, monoclinic, space group P21/n, a=13.404 (2) Å, b=22.732 (4) Å, c=13.932 (3) Å, β=113.134 (3)°, V=3 903.7(12) Å3, T=−120 °C, Z=4. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SASphosphine ligands / amine ligands / phosphate ligands / selenium / molybdenum cluster / 77Se-NMR spectroscopy  相似文献   

5.
<正> Mr=2548.12, Triclinic, P1, a=15.941(5), b=15.957(2),c=20.240(6)A, α=76.41(2),β=83.87(2),γ=74.41(2)°,V=4814.6A3, Z=4, Dc=1.757g.cm-3, Final R=0.053 for 11867 reflections. There are two crystallographically independent M1 type trinuclear Mo cluster molecules with 'loose coordination site', A and B, in an asymmetric unit of the title crystal. They are formulated as {Mo3S4(u-dtp)(dtp)3.PhCH2CN}(dtp=[S2P(OEt)2]-) and have essentially identical cluster molecular configuration, but differ from each other in the conformations for the phenyl rings of the ligands PhCH2CN. The lengths of the Mo-Mo bonds are 2.750(1), 2.753(1),and 2.768(1)A for molecule A and 2.742(1), 2.756(1), and 2.764(1)A for molecule B, while the dihedral angles betweem the phenyl ring and the {Mo3} triangle are 25.0° and 94.9° for A and B respectively.  相似文献   

6.
7.
Two new compounds containing molybdenum thiocyanide cluster anions, K6[Mo4S4(CN)12]·10H2O (1) and (18-crown-6K)8[Mo6S6(CN)16]·17.5H2O (2), were synthesized and investigated by X-ray structure analysis. Crystal data: a=11.8430(17), b=11.8430(17), c=35.170(7) , V=4932.8(14) 3, space group I41/a, Z=4, dcalc=1.563 g/cm3 for 1; a=28.7513(5), b=18.4190(3), c=20.7586(4) , =118.5982(7)°, V=9651.9(3) 3, space group C2/m, Z=4, dcalc =1.563 g/cm3 for 2. The [Mo4S4(CN)12]6- cluster anion in 1 has an ordinary structure typical of cubane transition metal complexes. In the structure of the [Mo6S6(CN)16]8- anion of 2, two crystallographically independent molybdenum atoms form a Mo6 metallocluster, represented as two edge-sharing tetrahedra.  相似文献   

8.
9.
Six new complexes, Mn(CO)( 5-C5H5){Ph2P(S)(CH2) n P(S)Ph2}] (1a3a) [(1a), n=1; (2a), n=2; (3a), n=3] and [Mn2(CO)4( 5-C5H5)2(cis--Ph2P(S)(CH2) n P(S)Ph2)] (1b–3b) [(1b), n=1; (2b), n=2; (3b), n=3] have been synthesized by the photochemical reaction of [( 5-C5H5)Mn(CO)3] with Ph2P(S)(CH2) n P(S)Ph2 [n=1, dppm(S)2; 2, dppe(S)2; 3, dppp(S)2]. The complexes have been characterized by elemental analysis, mass spectroscopy, f.t.-i.r. and 31P–[1H]-n.m.r. spectroscopy. The spectroscopic studies reveal that coordination of the ligand iscis-chelate bidentate in [Mn(CO)( 5-C5H5){Ph2P(S)(CH2) n P(S)Ph2}] (1a3a) and cis-bridging bidentate between two metals in [Mn2(CO)4( 5-C5H5)2(cis--Ph2P(S)(CH2) n P(S)Ph2)] (1b–3b).  相似文献   

10.
<正> The synthesis and crystal structure of the cubane-like cluste with [Mo3CuS4] core is reported herein. The title compound crystallizes i triclinic space group Pl with the following unit cell dimensions: a 11.723(3), b = 14.353(6), c = 15.533(4)A;α= 75.40(3)°,β=69.13(2)°,γ 64.93(3)°; Z = 2; V = 2196 A3; DC = 2.033 g·cm-3.7704 independent reflec tions were collected on CAM four-circle diffractoneter with MoKa radiatio in the range of 1 < <25°, with only 2083 reflections having intensitie I > 3σ(I). The structure was determined by direct methods and refined b the least-squares method to a final R index of 0.091. There are some distortion in the cubane-like [Mo3CuS4] core, with three Mo-Mo bonds and thre weak Mo-Cu bonds.  相似文献   

11.
<正> [Mo3S4(μ-CH3COO)[S2P(OEt)2]3(py)]·(CH3COOCH2CH3) , Mr = 1197. 96,monoclinic,P21/n,a=13. 158(2),b=23. 153(5), c=16. 175(3) A,β = 112. 79(1)°,V=4543. 1(7)A3,Z=4, Dc= 1. 751g/cm-3,λ(MoKa) = 0. 71073A ,μ= 13. 799cm-1,F(000) = 2408. Final R=0. 067 for 4000 reflections. The structure consists of the neutral cluster molecule [Mo3S4(μ-OAc) (dtp)3(py)] (dtp = [S2P(OEt)2]) and the solvent ethyl acetate (AcOEt). The three Mo-Mo bond lengths in the title compound are 2. 691(2) ,2. 747(2) ,2. 762(2) A ,whereas the Mo-N bond length in Mo(3) position is 2. 36(2)A. The important bond lengths of these Mo clusters with (py) ring at the loose coordination site are listed for comparison.  相似文献   

12.
Platinum(II) cyclo-hexamethylenedithiocarbamate (HmDtc) complex, [Pt{S2CN(CH2)6}2] (I), and its solvated form, Pt{S2CN(CH2)6}2] · CHCl3 (II), are synthesized and characterized by the 13C MAS NMR data. The HmDtc ligands in structure I are not equivalent, whereas the solvation of the complex is accompanied by the structural unification of the initially nonequivalent HmDtc ligands. In addition, the spectra are characterized by the 13C-195Pt spin-spin coupling. The noncentrosymmetric molecular structure of compound I determined by X-ray diffraction analysis includes two nonequivalent dithiocarbamate ligands coordinated by the metal in the S,S′-bidentate mode. The central atom forming the [PtS4] chromophore (intraorbital dsp 2-hybrid state of platinum) shifts from the plane of four sulfur atoms by 0.07 Å in the vertex of the flattened tetragonal pyramid. The seven-membered heterocycles ?N(CH2)6 of the HmDtc ligands are oppositely directed in space relative to the [S4] plane (trans orientation). The thermal behavior of compounds I and II are studied by simultaneous thermal analysis. In both cases, the final product of the multistage thermal destruction of the complexes is reduced metallic platinum.  相似文献   

13.
<正> {Mo4S4(μ-OAc)2(dtp)4H}3,(dtp=S2P(OEt)2),Mr=1371.60,Or-thorhombic, space group Pcab, a = 18. 90 (2) ,b = 21. 678 (4 ) , c = 24. 491 (4 ) A , V = 10031(7)A3,Z=8,Dc=1.818g/cm-3,F(000)=5464,λ(MoKa)=0.71073A,finalR= 0. 069 for 3738 independent reflections. This is a successful example of the formation of [Mo4S4]5+ from[3+1] reaction mode. The results of the structure determination indicate that the configuration of the title compound exhibits a tetranuclear cubane-type core [Mo4S4]5+ with six Mo - Mo distances in the range 2. 685~2. 969A and is very similar to that of the previously characterized compound {Mo4S4(μ-OAc)2(dtp)4}2, [Mo4S4]6+, which was obtained directly by the reaction of MoCl3·3H2O with dtp. Some notable differences, however, can be found when six Mo - Mo bond distances and bonding parameters of the four terminal bidentate ligands (dtp) are compared between these two compounds , That can be attributed to the difference in the oxidation state of these two clusters .  相似文献   

14.
Russian Journal of Coordination Chemistry - The anionic tantalum complex (ItBuH)[Ta(NMe2)3Cl3] (I) is synthesized by the reaction of [Ta(NMe2)3Cl2]2 with N-heterocyclic carbene ItBu and is isolated...  相似文献   

15.
我们合成了化合物{Mo[S_2CN(C_2H_5)_2]_4}~ {MoCl_6}~-,确定了其所属晶系、空间群及晶胞参数,并确定了重原子与其它全部非氢原子坐标等.  相似文献   

16.
By the reaction of cluster [Mo3OS3](dtp)4(H2O) used as starting material with CuI using [3+1] mode, two novel heterometallic-heterobridging cubane-type tetranuclear cluster compounds [CuMo3OS3]·I·(-OAc)[S2P(OC2H5)2]3·L [(I)L=py, (II)L=DMF] [dtp=S2P(OC2H5)2; OAc=OOCCH3] containing [CuMo3OS3] core have been obtained. Compounds (I) and (II) have been characterized by IR, EPR, UV-VIS, electrochemistry and X-ray crystallography. By comparison of these two compounds with the analogous [CuMo3S4] series in the structure and molecular orbital calculation, the influence of mixed S/O bridging on the structure is discussed. It is demonstrated that the {Mo3S3} cluster ring in [Mo3OS3]4+ possesses a similar quasi-aromaticity to [Mo3S4]4+. Crystal data: for (I), space group= ,a=13.781(8)Å,b=14.523(6)Å,c=12.098(6)Å, =98.37(4)°, =109.41(5)°, =105.00(5)°,V=2133(2)Å3,Z=2,R=0.058; for (II), space group= ,a=13.215(4)Å,b=17.818(8)Å,c=9.873(4)Å, =106.06(4)°, =109.78(3)°, =82.00(3)°,V=2100(2)Å3,Z=2,R=0.045.Invited Professor at Fuzhou University.  相似文献   

17.
Abstract

Seven-coordinate complexes of molybdenum(II) and tungsten(II) have become increasingly important as homogeneous catalysts. For example, the complexes [MX2(CO)3L2] (M = Mo and W; X = Cl and Br; L = PPh3 and AsPh3) have been shown to be catalysts for the ring-opening polymerisation of norbornene.1 Although a wide variety of complexes of the type [MX2(CO)3L2] (M = Mo and W; X = Cl, Br and I; L = nitrogen, phosphorus, arsenic and antimony donor ligands)2 have been reported, until now no examples of the mixed complexes [MX2(CO)3(py)L] have been prepared. In this communication we wish to describe the synthesis of the new mixed pyridine/L compounds [MI2(CO)3(py)L] (M = Mo and W; L = PPh3, AsPh3 and SbPh3).  相似文献   

18.
19.
The title compound [Cu(HSSA)(py)3H2O]n (H3SSA = 5-sulfosalicylic acid,py = pyridine) Ⅰ has been synthesized and structurally determined by single-crystal X-ray diffraction. Ⅰ was further characterized by elemental analyses,thermogravimetric analyses,IR and UV-visible spectroscopy. The crystal belongs to the monoclinic system,space group P21/c with a = 9.4564(10),b = 18.2679(19),c = 15.7284(12) ,β = 126.045(4)o,V = 2196.9(4) 3,Z = 4,Dc = 1.618 g/cm3,Mr = 535.02,μ = 1.141 mm-1,F(000) = 1100,λ(MoKα) = 0.71073 ,the final R = 0.0429 and wR = 0.1044 for all observed reflections. In the structure,every two Cu(Ⅱ) atoms are bridged by a bivalent 5-sulfosalicylic anion to form a 1D chain-like coordination polymer. Lattice waters between chains link them to form 2D layers which are further linked by C-H···O hydrogen bonds to form a three-dimensional supramolecular network.  相似文献   

20.
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