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1.
<正> Mr= 721.98,monoclinic, P21/n,a= 9.773(1), b = 6.641(3), c = 16.258(1)A,β=92.25(1)°,V=1054.4(7)A3,Dx = 2.274g/cm3,Z=2,λ(MoKα)=0.7107A.Final R= 0.024,Rw= 0.036 for 1554 observed reflections. The cluster core Fe2Mo2 is a rhombic plane with Mo-No distance of 2.827A and average Mo-Fe distance of 2.773A.  相似文献   

2.
<正> (η5-C5H5)W2Fe2(μ3-S)2(CO)8,Mr = 897. 80,monoclinic,C2/c,a= 18. 019 (2),b = 8. 330(1),c= 16. 043(2) A ,β= 114. 30(1)°,v = 2194. 7(6)A3,z= 4, Dx = 2. 717g/cm3, A(MoKa) = 0. 71037 A , μ= 122. 01cm-1, F (000) = 1656, T = 295K,R=0.056,Rw = 0. 059 for 1250 observed reflections. The crystals of the title compound are isomorphous with the analog (η5-C5H5)2Mo2Fe2(μ3-S)2(CO)8.  相似文献   

3.
<正> Mr = 984. 63, orthorhombic Imm2, a = 14.562(3), b = 10.391(1), c = 7.139(4) A; V = 1080.2(1) A3, Z = 2, DC = 3.027 g.cm-3. Final R= 0.022 for 620 reflections with I > 20(Ⅰ). In the title compound, four metal atoms form a butterfly configuration, one ,μ-Te is bonded to these four metals and two μ3-Te cap two Fe-Mo-Mo faces. All these atoms as a whole give a bicapped trigonal bipyramidal structure.  相似文献   

4.
<正> The title compound belongs to triclinic system, space group PI, with dimensions: a = 9.237(1), b = 9.589(1), c = 10.424(1) A ; <*= 72.09(2)?ft- 88.79(2)? 3r=80.28(l)? Z = 2, V = 865.5 A3, Dx = 2.626 gcnr3. Final R = 0.026 and Rw = 0.036 for 2531 reflections.  相似文献   

5.
<正> C20H40Mo3NO8P3S10, Mr=1123.93, triclinic, P1,a=12.972(3), b=13.763(2), c= 14.515(7)A,α=66.22(3),β=101.72(3),γ=118.90(1)° , V= 2076(2) A3, Z=2,Dc=1.798 g.cm-3, MoKa radiation, final R= 0.040 and Rw=0.056 for 5645 observed reflections. The molecule contains three Mo atoms arranged in a triangle with one capping-S atom, three (μ-S) atoms, one (μ-EtCOO) ligand, one chelate ligand dtp on each Mo atom, and one terminal Py on atom Mo(1). The coordination of Mo atoms is of distorted octahedron.  相似文献   

6.
The reaction of Fe_2(μ_3-Te)_2(CO)_9 with Mo_2(CO)_6(η~5-C_5H_5) affords the title compound. Its X-ray analysis shows a butterfly structure for the Mo_2Fe_2 core; the two molybdenum atoms occupy the hinge with a Mo—Mo bond distance of 2.819 and the two iron atoms are on the tops of the wings with an average Mo—Fe bond distance of 2.932(2). Each molybdenum is bonded to a Cp ring, and three CO ligands are terminally bonded to each iron atom. One tellurium atom quadruply bridges Mo_Fe_2 with Mo—Te(μ_4)=2.625(2). and Fe—Te(μ_4)=2.713(2). Two tellurium atoms triply bridge the two triangular Mo_2Fe faces with Mo—Te(μ_3)=2.678(1) and Fe—Te(μ_3)=2.513(3). The molecule has C_(2v) symmetry and a bicapped triangle bipyramidal skeleton. Crystallographic parameters are as follows: space groupImm2(orthorhombic), a=14.562(3), b=10.391(1), c=7.139(4), V=1080.2(i)~3, Z=2, ρ(cald)=1.819g·cm~(-3). The final R factor was 2.2% for 620 independent reflections(I>2σ(I)).  相似文献   

7.
Under suitable reactant ratios without sublimation or reerystallization, single crystals of(η~5-C_5,H_5)_3 Ln-OC_4H_8(In = La, Pr, Nd) could be prepared by the reaction of cyclopentadienylsodium with respective lanthanide trichlorides in THF. Using low temperature technique wehave collected the X-ray data of single crystals of the title compounds at -60℃ under N_2and determined crystal structures. (η~5-C_5H_5)_3 Pr·OC_4H_8, [(η_5-C_5H_5)_3 Nd·OC_4H_8] recrystallizesin the monoclinic space group P2_1/n[P2_1/n] with unit cell parameters a = 8.406(3) [8.364(3)],b = 24. 510(9) [24.467(9)], c = 8. 284(3) [8.254(3)] A, β= 101.60(3) [101.42 (3)], D_c = 1. 62 [1.65]gem~(-3) for z = 4 [4]. Least-square refinement has led to a final R value of 0.056 [0.063],R_W = 0.049 [0.062]. The THF molecule is coordinated to the Pr [Nd] atom at a Pr-O [Nd-O]bond length of 2.16(1) [2.54(1)], A. The Pr-C (Cp) [Nd-C(Cp)] bond distances average 2.80(2) [2.78(2)] A. The title compounds are isostructaral with (η~5-C_5H_5)_3  相似文献   

8.
<正> The title compound is orthorhombic, space group Pbn2 , with a=12.172(5), b=13.595(2), c=12.924(4), V=2138.5(2) ~3, z=4, Dx=2.749 g/cm~3. The octahedral-shaped black crystal was selected for data collection on a CAD-4 diffractometer, using graphite monochromator Moka radiation (λ=0.7107), ω-2θ  相似文献   

9.
<正> Cluster compound [Mo4(μ3-O)2O4Cl2(o-CH3C6H4COO)6] has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid. It crystllizes in the orthorhombic space group Praia with cell parameters:Mr= 1361. 6,a=13. 792(4), b=17. 957(3),c= 20. 974(9) A ,V=5194(2) A3,Z= 4,Dc= 1. 74g/cm3,F(000) = 2704,μ(MoKa) = 11. 0/cm. The final R=0. 061 and Rw=0. 064 for 1441(I>3oooooooooo(I)) observed unique reflections. The tetranuclear complex molecule, where the molybdenum atoms are bridged by two μ3-O atoms and six bidentate o-methylbenzoato ligands,is located at crystallographic two-fold axis(x,-1/4,1/4) with one Mo-Mo bond of 2. 610A  相似文献   

10.
All attempts to prepare light lanthanide dicyclopeutadienyt chloride failed,due to the disproportionation reaction. The crystal complex of [(η~5-C_5H_5)_2NdCl.OC_4H_8]_2 was successfully prepared by the reaction of NdCl_3·2C_4H_8O with cyclopentadienyl sodium (molar ratio 1:1.8)in tetrahydrofuran at room temperatureThe composition of the title compound was determined by the methods of elemental analysis, infrared spectroscopy and photoelectron spectroscopy. The crystal structure of [(η~5-C_5H_5)_2NdCl·OC_4H_8]_2 was determined from single crystal X-ray diffraction. Data were collected at-60℃ under dry nitrogen atmosphere.The complex crystallizes in the monoclinic space group P2_1/c,with Z=2. Lattice parameters are: a=8.201(3), b=21.589(6),c=8.596(3),β=109.10(3)°.The structure was solved by Patterson and Fourier techniques and refined by least-squares to a final conventional R=0.0636 for 1680 reflections. There are two Nd atoms in the dimeric unit which are bridged asymmetrically by the two chlori  相似文献   

11.
Treatment of tricarbonyl cyclopentadienyl metal (molybdenum or tungsten) chloride with equal molar amounts of tricarbonyl nitrosyl iron sodium at room temperature yielded the following complexes: orange (η5-C5H5)M(CO)2NO, violet [(η5-C5H5)M(CO)3]2 and black (η5-C5H5)M(μ3-NH)(μ2-NO)(μ2-CO)Fe2(CO)6. These were separated and purified by column chromatography. The last black complexes have a new cluster-type structure with a face-bridging imido(μ3-NH) ligand which was obtained by reducing the nitrosyl (NO) group. In this paper, synthesis and characterization of the title complexes are reported along with their crystal structures which are of two types.  相似文献   

12.
The di(η~5-cyclopentadienyl)lutetium chloride was first prepared by Dubeck et al.in 1963.However,to our knowledge no report on its structrual information has beengiven up to date.The crystal structure of its four analogies which exist as chlorine-bri-  相似文献   

13.
<正> The title complex crystallizes in the orthorhombic space group Pna21 with Mr = 570. 8, a = 16. 927(6), b = 18.942(7), c=10. 618(5)(?) and Z = 4. The structure was solved by Patterson and Fourier techniques and refined by block-diagonal least squares techniques to R = 0. 090 and Rw = 0. 093 for 1553 reflections with I>1. 5σ(I). The Pr3+ ion is bonded to five carbon atoms of cyclopentadi-enyl ring, four μ-chlorine atoms and one oxygen atom of THF in an octahedral geometry with the Pr-C distances in the range 2. 6.7 - 2. 79(?)(av. 2. 76(?)) , the Pr-Cl distances in the range 2. 81 - 2. 92(?) (av. 2. 86(?)) and the Pr -O distance of 2. 51 (?). Each Li+ ion is coordinated by two μ-chlorine atoms and two oxygen atoms from THF in a tetrahedral geometry with the Li-Cl distances in the range 2. 24 - 2. 61(?) (av. 2. 43(?)) and the Li -O distances in the range 1. 86-1. 94(?)(av. 1. 91(?)). The Pr atom and the two Li atoms are bridged asymmetrically by the chlorine atoms.  相似文献   

14.
Synthesis of complexes(η~5-CH_3C_5H_4)M(CO)_2NO(M=Mo,I;M=W,II)and clusters(η~5-CH_3C_5H_4)M(μ~3-NH)(μ~2-NO) (μ~2-CO)Fe_2(CO)_6(M=Mo,III:M=W,IV),based on the reaction of (η~5-C5_H_4)M(CO)_3Cl with Na[Fe(CO)_3NO] at room tem-perature,have been demonstrated,The crystal structures of II and IV arealso presented.  相似文献   

15.
本文用Fe_3(μ_3-Te)_2(CO)_9同Mo_2(CO)_6(η~5-C_5H_5)_2反应合成出标题化合物。结晶学参数如下:空间群Imm2,620个I≥2σ(I)的独立衍射参加最小二乘法修正结构,最终R因子值为0.022。X射线分析表明Mo_2Fe_2形成一蝴蝶型结构,其中两钼原子占据两蝴蝶翼的交界处,Mo—Mo=2.819。两个铁则处于蝴蝶翼的顶端,Mo—Fe=2.932(2)。每个钼原子与一个环成二烯基键联,三个羰基配体以端基的形式与每个铁原子键联。一碲原子处在蝴蝶型开口的上方键联四个金属原子,Mo—Te(μ_4)=2.625(2),Fe—Te(μ_4)=2.713(2)。两个μ_3-碲原子处在μ_4-Te原子的对面,分别处在二个FeMo_2三角面上,Mo—Te(μ_3)=2.678(1),Fe—Te(μ_3)=2.513(3)。整个分子具有严格的C_2v对称性,整个簇骼结构可看成双帽三角双锥构型。  相似文献   

16.
<正> The crystal of (C5H9C5H4)Er4(μ2-Cl)6(μ3-Cl)(μ4-O)(THF)3 belongs to triclinic space group P1, with a = 11. 909(4), b = 15.343(5), c=15. 619 (4)(?), α=104. 18(2), β=98. 81(3), γ= 111. 06(2)°, V = 2486(1)(?)3, Z = 2, Dc = 2. 07g/cm3, λ(MoKα) = 0.71073(?), μ= 73. 4cm-1, F(000) = 1476, Mr=1549. 25. The structure was solved by Patterson and Fourier techniques and refined by block diagonel least-squares method to final R = 0. 078 and Rw = 0. 084 for 5594 reflections with I≥1. 5σ(I). The results revealed that the complex is composed of four Er atoms bridged by seven Cl and one oxygen atoms with three of the Er atoms bonded each to a cyclopentylcyclopentadienyl group, and one Er atom, bonded to three THF. The Er atoms constitute a pseudo-tetrahedron.  相似文献   

17.
1 INTRODUCTION The chemistry of transition metal cluster has enjoyed an exceptional growth since the mid 1970s[1, 2], especially in recent years the structural and bonding aspects of mixed-metal tetrahedral skeleton clusters have been extensively studied[3]. One important reason is that such chiral cluster can induce an asymmetric catalysis potentially. In our research group, considerable efforts have been directed to the synthesis of chiral tetrahedral clusters containing four different…  相似文献   

18.
<正> The title compound was prepared by reaction of Mo3(μ3-O) (μ-S)3-(dtp)4 (H2O) with C6H5COONa and pyridine. C27 H35 Mo3NO9P2S7, Mr = 1091.76, monoclinic, space group P21/c, a = 15. 057(5), b = 13. 052(5), c = 21. 662(6)(?), β=105.97(2)°, V = 4093(2) (?)3, Z = 4, Dc= 1. 77gcm-3, F(000) = 2176, μ(MoKα)=13.50cm-1, final R =0. 068 for 2835 observations. The molecular configuration is new and of approximate C, symmetry, and there are two C6H5COO bridging groups in the structure. The three Mo atoms form an isosceles triangle with three sides of 2. 567(3), 2. 576(3), and 2. 649(3)(?), where the two Mo-Mo bonds bridged by C6H5COO group are much shorter than that without. Something about the reactivity of Mo clusters is discussed.  相似文献   

19.
含Ⅵ主族的混合金属原子簇化合物可作为重要的催化剂,这种催化剂在均相催化方面,由于异核原子簇中不同金属具有不同的反应性,可能表现出独特的催化性能,特别是Mo-Fe-S原子簇化合物,除了可作为加氢脱硫的催化剂外,又可能是固氮酶活性中心的模型物,  相似文献   

20.
<正> Introduction. In an attempt to synthesize Mo cluster compounds from the high-valenced Mo compounds in P_2S_5/EtOH-HC1 system we have obtained a brownblack rhombohedral crystal. The composition of it Mo_2O_3[S_2P(OC_2H_5)_2]_4 has been confirmed by X-ray single crystal structure determination, which reveals that the crystal structure is different from that by Knox, J. R. & Prout, C. K. (1969).  相似文献   

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