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1.
<正> INTRODUCTION. The Fe_4S_4 cubane-like clusters have been extensively studied as the model compounds for the active center of the Fe-S proteins in the last fifteen years. Coucouvains et al. have recently reported the syntheses and structures of a few Fe_4S_4 cluster compounds containing R_2NCS_2(R_2dtc) and RS (or Cl) mixed terminal ligands and having [Fe_4S_4]~(2+) core oxi-  相似文献   

2.
<正> (Et4N)4[Mo2Fe7S8(SPh)12] : Mw=2670.3, triclinic, p1, a=12.775(4), b=13.076(3), c=20.576(4)A, α=80.00(2), β=81.39(2), γ=61.51(2)°, V=2966.3(14) A3, Z=1, D=1.494 gcm-3, R=0.077 for 4031 observed reflections. The complex was prepared by reactions of (Et4N)2[Fe4(SPh) 10] with (Et4N)2MoS4 in an ace-tonitrile solution. The structure of [Mo2Fe7S8(SPh)12]4- anion is a double-cubane-like configuration bridged by a Fe(SPh)6 group.  相似文献   

3.
The crystal structure of .[Et4N][Sm(S2CNEt2)4] was determined by X-ray diffraction technique. The crystal crystallizes in monoclinic system, space group P21/n with a= 1. 1695(3), b=2.0821(6), c=1.7420(7) nm, β=99. 79(3)°? Z=4, Dc= 1. 39 g/ cm3, μ(Mo/KTσ) = 18. 4 cm-1, F(000) = 1812. The structure was solved by Patterson and Fourier techniques and refined by least-squares method to a final conventional R of 0. 053 for 3116 (Ⅰ> 3σ- (Ⅰ)) reflections. Each asymmetric unit contains two ions [Sm (S2CNEt2)4]-1 and [Et4N] +1, having distance between central atoms N5 and Sm3+ to be 0. 6522 nm. The atom Sm is coordinated by eight sulphur atoms. The Sm-S distance lies in the range of 0. 285-0. 290 nm with an average of 0. 288 nm.  相似文献   

4.
<正> Since the discovery of iron-sulfur proteins , a number of analogous compounds of the active sites of iron-sulfur proteins has been synthesized and characterized . Due to the similarity between sulfur and selenium, some selenoproteins with similar active site as iron-sulfur proteins were found . We have synthesized a series of iron-selenium compounds in correlative study with the iron-sulfur compounds. In this paper, we will discuss the syntheses and crystal stuctures of the title compounds. The spectroscopic properties of these compounds have been under investigation.  相似文献   

5.
<正> Introduction. A series Of Mo-Fe-S complexes with doublecubane structure has been synthesized and identified. Because of the similarity of its extended X-ray absorption fine structure (EXAFS) to that of FeMo cofactor and nitrogenase, suggestion has been made that the doublecubane complexes may serve as models for the Mo site of nitrogenase. Therefore, the investigation of this type of complexes has attracted much attention. By using the similar method of spontaeous self-assembly reaction, and starting from certain kinds of Mo-Fe-S compounds, we have been able to obtain several kinds of compounds, one of which  相似文献   

6.
<正> [(C2H5)4N]2[Mo2o2S2(S2)2], Mr = 676. 74, monoclinic, P21/c, a = 13.510(2), b = 14.373(2), c=14. 777(3)(?), β = 97.53(2)°, V = 2844.7(9) (?)3, Z = 4, Dc= 1. 58g/cm3, μ(MoKα) = 13.0cm-1, F(000) = 1384, R =0. 033 for 1803 observed reflections. The structure contains discrete [Mo2O2S2(S2)2]2- anions and Et4N+ cations. The two oxygen atoms bonded to the Mo atoms are in cis-form with respect to the Mo2S2 bridging unit, with an average Mo- O distance of 1. 678 (?), The Mo…Mo distance is 2. 832(1)(?).  相似文献   

7.
<正> The title compound crystallizes in orthogonal space group P212121with α= 12. 848 (5), b =13. 227 (3), c = 29. 519(8) A ,Z = 4 , V= 5016. 5 A3 and Dc = 1. 483g/cm3. 4940 independent reflcctiions were collected on a CAD4 diffractometer with MoKa radiation in the range of 1°<0<25°,of which 3559 reflections having intensities I >3σ(I) were used for structure determination. The structure was solved by direct methods and refined by the least-squares method to final discrepancy factors R=0. 071 and Rw - 0. 075. The anion of the title compound can be described as a slightly distorted MoS42-tetrahedron coordinated by three [CuS2CNEt2] units ,with the four metal atoms lying approximately in a plane.  相似文献   

8.
<正> [Et4N]2 [WCu3S4 (S2CNEt2)3], Mr = 1172. 01, orthorhombic, space group P212121 with a=12. 858(9),b=13. 204(5) ,c=29. 501(9) A ,V=5008. 7 A3, Z = 4, Dc = 1. 55gcm-3, μ(MoKa) = 40. 3cm-1. The final R and Rw are 0. 069 and 0. 075, respectively, for 3072 observed unique reflections. The anion contains a slightly distorted WS42~ tetrahedron coordinated by three CuS2 CNEt2 units,with four metal atoms lying in a plane.  相似文献   

9.
<正> Introduction. Previously, we have reported the compound α-(Et_4N)_3[Fe_3(SPh)_3-Br_3Cl_3](Ⅰ)~1 with C_2 symmetry. An isomer(Ⅱ) of this compound, which has D_3dsymmetry, is reported in this paper. Brow-green crystals of Ⅱ is obtained from the reaction of FeCl_2, PhSNa and Et_4NBr (1:1:1) in acetonitrile solution.  相似文献   

10.
The single crystal of [Et4N]4 [MO2Fe4S9(SCH2CH2S)2] was obtainedby reaction of (NH4)2HoS4, FeCl3 , HSCH2CH2SH and Et4 NBr in CH3CN and MeOH-MeONa. Cluster compound [Et4N]4 [Mo2Fe4S9(SCH2CH2S)2] crystal -Lized in the monoclinic space group C2/c with unit cell parameters:a = 17. 672(2)A, b = 33. 851(4)A, c = l3. 900(3)A, β=135.11(4)°, V=5868.8 (3.9)A3 and Z = 4. On the basis of 3514 unique data (I>2σ(I)) the structure was refined to R = 0.0575. The anion [Mo2Fe4S9(SCH2CH2S)2]4-of the cluster compound includes doubly bridging (μ2-S), triply bridging (μ3-S) and quadruply bridging (μ4 -S) . The structrue analysis gives a rule with bond lengths decreasing in the order of Fe-(μ4-S)> Fe-(μ3-s)> Fe-(μ2 -s) and EHMO calculation gives the other rule with bond order increasing in the order of Fe-(μ4-S)< Fe-(μ3-S)相似文献   

11.
<正> Fe_2OSsN_2C_(52)H_(70),Mr=1043.23,monoclinic, P21/a, a=18.121(3), b=15.249(3), c=20.369(4)A,β=102.49(8)°,V=5495(1)A3, Z=4, Dc=1.261g.cm-3,MoKα(λ =0.710691), μ=17.816mm-1, F(000)=2208. R=0.073 for 4374 observed reflections with I≥3.0σ(I). The structure of the anion contains a linear Fe-O-Fe unit, with mean Fe-O distance of 1.766(2)A. The coordination geometry about each iron atom is close to tetrahedral with the angles O-Fe-S and S-Fe-S being 115.3° and 103.1°, respectively.  相似文献   

12.
ZnCl2, PhONa和Et4NCl稨2O在乙腈溶剂中反应合成了一种二核锌配合物[Et4N]2[Zn2(OPh)2Cl4]。X射线衍射结果表明,晶体属单斜晶系,C2/m空间群,晶胞参数 a = 14.1366(2), b=13.6985(5), c=9.3308(3)牛?107.851(2)o, V=1719.92(9)?,C28H50O2N2Zn2Cl4,Mr=721.24,Z=2,Dx=1.393g/cm3,μ(MoKα)=1.732mm—1,F(000)=756, R=0.0552, wR=0.1534, S=1.027。 配合物是由2个阳离子Et4N+和1个阴离子[Zn2(OPh)2Cl4]2—组成。阴离子[Zn2(OPh)2Cl4]2—包含着1个中心Zn2O2菱形平面。配合物中的2个锌原子通过2个苯酚中的氧原子桥连,每个锌原子还与2个氯原子配位形成变形四面体结构。  相似文献   

13.
<正> The title compound was synthesized and crystal structure was solved. (Et4N)3[Mo2Fe6S8(OMe)3(SPh)6], Mr=1922.39, hexagonal, PGs/m, a = 17.750(3), c=15.880(2) A, V=4332.7(26) A3, Z-2, Dx=1.477 g/cm3, MoKα, λ= 0.71069 A, R = 0.059, Rw = 0.065, for 814 observed reflexions. The complex anion contains two Fe3MoS4 cubane-like units linked throug their molybdenum atoms by three ,μ2-methoxy-groups, and the overall structure of the anion has C3b symmetry.  相似文献   

14.
<正> The title compound was synthesized and its structure solved. The formula is [Et4N]3[Fe3(SPh)3Br3Cl3]. M=1231.95, monoclinic, space group C2/c, a=24.569(4), b=13.504(2), c=18.348.(3)A, β=110.78(1)°, V=5691(3)A3, Z=4, Dm= 1.41, Dc=1.44-g/cm3. The flat structure of the anion has. a planar [Fe3S3] ring and three phenyl groups. Statistical distribution of chlorine and bromine atoms on two sides of the [Fe3S3] plane results in a C2 symmetry of the anion.  相似文献   

15.
[Me4N]10[Fe4(OH)4(PW10O37)2] · 15H2O was synthesized by the reaction of FeCl3 ·6H2O, with △-Na8HPW9O34 and Me4NBr. Crystal data: M = 6225.75, space group P21/c with the monoclinic parameters: a = 1.3228(5), b = 3.5634(3), c = 1.5226(2) nm, β = 94.20(2)°, V = 7.1576nm3, 7 = 2,DC = 2.888 g/cm3, Mo Kαradiation (λ = 0.071069 nm), μ= 168.534 cm-1, F(000)=5576, final R = 0.0428 and Rw = 0.1204 for 7086 observed reflections with I > 2σ( I) . The structure of the title compound is the first structurally characterized heteropolymetalate with hydroxo-bridging metal aggregation Fe4OH4 encapsulated in the dimer of Keggin polyoxoanion.  相似文献   

16.
Awell-groundmixtureof犤NH4犦2犤MoS2O2犦,CuI,andEt4NBr,wasputintoareactiontubeandheatedat80℃for4hunderanitrogenatmosphere.AfterextractingtheresultantblacksolidwithCH3CN,theextractwasfilteredtoaffordadeepredfiltratewhichcontainsatwin-nestshapeinter-mediate犤NEt4犦4犤Mo2O2S6Cu6I4Br2犦1犤1犦.Twin-nestshapeproductsareinterestingbecausetheirbridgegroupscleavagecanincorporatedifferentligandsintotheclusterspecieswithinterestingskeletalstructures.Takingadvantageo…  相似文献   

17.
<正> [Me4N]6[Ag6(i-mnt)6].H2O(1),[Et4N]4[Cu8(i-mnt)6](2) and [Me4N]4-[Cu5Ag3(i-mnt)6].H2O(3)(i-mnt=S2C=C(CN)2) were synthesized. The crystal and molecular structure of the complex 1 was reported by us.The structure of the complex 2 was determined from single crystal X-ray diffraction data. [Et4N]4[Cu8(i-mnt)s] 2, Mr=1870.46, monoclinic, P21/n, a=14.724(6), b = 17.228(3), c=15.59(1)A,β= 100.75(7)°,V=3886.3A3;Z = 2,Dc= 1.598 g/cm3. Complex 3 has been characterized by ICP elemental analyses and IR spectrum.  相似文献   

18.
A dinuclear molybdenum(V) cluster compound (Et4N)2[Mo2S4(i-mnt)2] (i-mnt=l,l-dicyanoethylene-2,2-dithiol, (S2C=C(CN)2]2-) has been prepared by the ligand substitution reaction of Mo2S4(iso-pr2dtp)2 (iso-pr2dtp=S2P(OC3H7)2-) with K2(i-mnt) in the presence of Bt4NI. This cluster was characterized by inrrared spectrum, UV-Vis spectrum and single crystal structure analy-sis. The cluster anion [Mo2S4(i-mnt)2]2- possesses C, symmetry with a crystallographic mirror plane through two bridging S atoms. By the S....S supramolecular interactions between two adjacent cluster anions the [Mo2S4(i-mnt)2]2- anions are linked to form infinite chains along the b axis. Crystal data: monoclinic, space group C2/m, a=1.8748(6), b=1.5360(4), c=1.4322(5) nm, ,β=112.02(2)°, V=3.823(4) nm3, Z=4, Dc=1.50 g/cm3. The final R=0.038 and .RW=0.053 for 3015 observed unique reflections.  相似文献   

19.
<正> (Et4N)2[Et2NCSSMoS2)2O3Fe2S2]·DMF(1) ,Mr= 1174. 10,mono-clinic,space group P21/n,a = 9. 608(3),b=17. 962(2),c=15. 312(3) A ,β=95. 03 (3)°,V=2632. 4 A3,Dc= 1. 48 g/cm3 and Z=2. The structure was solved from 2499 reflections with I>3σ(Ⅰ) and refined by full-matrix least squares method to R(Rw) = 0. 073(0. 087). The anion of 1 has linear Mo -Fe -Fe-Mo array. The oxidation states of metal atoms in this cluster are 2Mo(Ⅵ) + 2Fe(Ⅲ).  相似文献   

20.
本文通过对巯基铁与MoSi_4~(2-)反应的研究,对双立方烷型铁-钼-硫原子簇化合物的形成途径及中间物作了讨论.同时报道了[Fe_4(SPh)_(10)](Et_4N)_2与[MoS_4][Et_4N]_2反应的产物(Et_4N)_(4~-)[Mo_2Fe_7S_8(SPh)_(12)](2)的合成、晶体结构、红外光谱和磁化率.晶体2属三斜晶系,M_r=2670.3;空间群PI;α=12.775(4),b=13.076(3),c=20.576(4)A;α=80.00(2)°,β=81.39(2)°,γ=61.51(2)°;V=2966.3(14)A~3;Z=1;D_c=1.495g·cm~(-3);F(000)=1378;偏离因子R=0.077.特别指出了分子中Mo—Mo’的距离[7.188(6)A]是当今同类化合物中最长的,它对研究固氮酶活性中心模型物的合成和结构规律,有重要意义.  相似文献   

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