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1.
<正> The crystal and molecular structure of [Li+(DME)3]2[(CpNd)4 (μ2-CH3)2(μ4-O) (μ2-Cl)6]2~was determined from single crystal X-ray diffraction. The complex crystallizes in the monoclinic space group P21/n with lattice parameters a= 14. 614(5), b= 18. 683 (5),c= 24. 595 (6) A, β = ,91-85(2)°, V = 6712(3) A3,2 = 4,DC = 1. 63g/cm3,F(000) = 3256,Mr=1650. 85. The structure was solved by direct methods and Fourier techniques and refined by least-squares to a final R=0. 047,RW = 0. 049 for 3761 with I>3σ(I). The result revealed that the anion [(CpNd)4(μ4-O) (μ2-Cl)6(μ2-CH3)2]2- is composed of four neodymium (Ⅲ) atoms bridged by six Cl atoms, two methyl groups and one oxygen atom, and every Nd is bonded to a cyclopentadienyl group. The four Nd atoms form a distorted tetrahedron. The cations are composed of two Li+(DME)3 with average Li-O distance of 2. 120(40) A.  相似文献   

2.
<正> Mr=996.91, triclinic, P1, a=8.773(2), b=9.712(3), c=13.652(1) A; α=69.24(0), β=70.43(3), γ=66.87(l)°; Z=l, Dx=1.699 g/cm 3. Final R=0.053 for 3186 reflections with I≥3a(I). There is an interesting trans influence of μ-s bridge in this binuclear cluster. Mo-Mo distance is 2.752(1) A.  相似文献   

3.
Crystal structure of the title complex was determined by X-ray diffraction method. It crystallizes in space group P21/n with cell dimensions:α=10. 041(5) , b=10. 719(4) , c= 1. 5671(6) nm, β=104. 36(3)°. The structure was solved by Patterson method. The final residual factor is R=0. 050.  相似文献   

4.
<正> Introduction. The complexes of Mo(V) and oxalate are found to exist in several various configurations. As an anologous compound for the activecenter of Mo enzymes they have attracted broad attention. It was found by Sobczak and Ziolkowski in 1976 that these types of complexes had a higher catalytic selectivity in the epoxidation of olefine by hydroperoxides  相似文献   

5.
<正> The molecular and crystal structure of the complex (μ-HOCH2CH2-S)2 Fe2(CO)4(PPh3)2 synthesized by reaction of ethylene epoxide with (μ-Lis)2Fe2(CO)6, followed by EtOH alcoholysis and PPh3 substitution,was determined by X-ray diffraction technique. The crystals are triclinic,space group P 1,with a= 10. 902(2),b=12. 106 (2),c=16. 123(4) A ,V= 2079. 36A3,α=78. 13(1),β=89. 37(2),γ=87. 93(1)°, Z = 2,Dx=1. 44 g/cm3.μ(MoKa) = 9. 149cm-1, F(000) = 940. The final R and Rw equal to 0. 055 and 0. 068,respectively,for 3598 observed independent reflections. In this molecule two PPh3 ligands are trans to the Fe - Fe bond and axially coordinated to two iron atoms. In addition,two hydroxylethyl groups are attached to bridging sulfur atoms by e-type of bond and thus this molecule is an ee conformer.  相似文献   

6.
A new dianionic guanidinate bridged diamide ytterbium(Ⅲ) complex {[Me2Si(NPh)2]2Yb[(NiPr)2CN(SiMe3)2]}{Li(THF)2}2 was synthesized by the reaction of bisguanidinate ytterbium chloride [(SiMe3)2NC(NiPr)2]2Yb(μ-Cl)2Li(THF)2 with silylene-bridged diamide lithium PhLiNSiMe2NLiPh.The complex was characterized by elemental analysis and IR.The molecular structure was further determined by X-ray diffraction techniques.The crystals are monoclinic,space group p 21/c,a=14.0001(8),b=17.6808(9),c=24.9565(16),β=95.994(3)...  相似文献   

7.
<正> M=1140.85, monoclinic, P21/c. a=12.748(2), b=14.320(2), c=23.118 (3)A,β=101.07(1)°, V=4141(2)A3, Z=4, Dc=1.830 g.cm-3. Final R=0.039 for 4160 reflections.The title compound is a rather irregular trinuclear molybdenum cluster having only two M-M bonds with two shorter Mo-Mo distances of 2.808(1), 2.839(1), and one longer Mo-Mo distance of 3.337(1)8. The existence of two Mo-Mo bonds is coincident with the electron counting for {Mo3} cluster core, and may be regarded as a result of the oxidation of a compound Mo3(μ3-S)(μ-S)2 (μ-L)[S2P(OEt)2]4(L') (L'=neutral ligands)1 characterized by us previously.  相似文献   

8.
从均相Ziegler-Natta催化剂分离出有催化聚合活性的[Al_3Nd_6(μ_2-Cl)_6(μ_3-Cl)_6(μ_2-Et)_9Et_5OPr~i)_2单晶,并用X光衍射法测得其晶体结构.结果表明,该单晶是由多核Nd-Al双金属配合物的二聚体组成,属三斜晶系;晶体的空间群为PI.晶胞参数α=15.196(6),b=15.263(5),c=13.749(4)A;α=90.01(2),β=95.12(3),γ=82.65(3)°;V=3149.5A~3;Z=1.Nd原子的配位数是7,构型为单帽三棱柱.Nd原子由三重和二重氯桥连成分子骨架.本文对双金属配合物的催化活性中心也进行了讨论.  相似文献   

9.
魏丹毅  郑岳青  林建利 《化学学报》2002,60(7):1248-1252
在甲醇与水的混合溶剂中,经浓硝酸硝化的Ho_2O_3与1,10-邻菲啰啉反应形 成氢氧根桥联的双核钬配合物[Ho_2(phen)_4(H_2O)_4(OH)_2] (phen)_2(NO_3)_4 (phen = 1,10-邻菲啰啉)。单晶X射线衍射晶体结构测定表明晶体属三斜晶系, P1-bar (no. 2)空间群,晶胞参数a = 1.1241(1) nm, b = 1.1439(1) nm, c = 1. 4058 (1) nm, α = 93.989(7)°, β = 98.173(7)°, γ = 108.19(1)°, V = 1.6874(4) nm~3, Z = 1, D_c = 1.737 g/cm~3, F(000) = 880,7752个独立衍射 点中,5702个可观测点满足F_o~2 ≥ 2σ (F_o~2),R_1 = 0.0499, wR_2 = 0. 858。标题配合物由中心对称的双核[Ho_2(phen)_4(H_2O)_4-(OH)_2]~(4+)配阳离 子,邻菲啰啉phen分子及硝酸根NO_3~-阴离子组成。敏个稀土原子与2个邻菲啰啉 配体,2相水分子和2个氢氧根配位形成配位数为8的[HoN_4O_4]四方反棱柱。配位 多面体通过两氢氧根基团形成共棱的[Ho_2N_8O_6]双四方反棱柱[d(Ho-N) = 0. 2549~0.2565 nm, d(Ho-O_(H_2O) = 0.2356, 0.2366 nm, d(Ho-O_(OH)) = 0. 2223, 0.2240 nm]。通过氢键和芳环堆积作用,配阳离子和邻菲啰啉分子排列形成 平行于(10 1-bar)的两维层结构,NO_3~-阴离子位于层之间。标题配合物为顺磁 物质,在5 ~300K区间内遵循Curie-Weiss定律X_m (T + 4.43) = 14.72 cm~3·K ·mol~(-1)(X_m为每摩尔Ho~(3+)离子磁化率),其Ho~(3+)离子的室温有效磁矩为 10.76 B. M.,与Ho~(3+)自由离子的磁矩基本相同,表明稀土离子间不存在磁交换 作用。  相似文献   

10.
<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   

11.
<正> M=1013.98, hexagonal, P63/m, a=b=15.492(2), c=8.530(4)A, γ=120°, V=1773A3, Z=2, Dc=1.899°g.cm-3. Final R=0.042 for 611 reflections.This is a Bl(bicapped) type trinuclear molybdenum cluster with two S capping atoms located on the 63 axis and exhibits full D3h symmetry. The Mo-Mo distances are 2.606(1)A, with a bond order of 11/3. It is paramagnetic.  相似文献   

12.
Inthepastfewyears,nearly50kindsofrareearthcomplexeswithaminoacidswerestructurallycharacterizedl.AllofthesecomplexesweresynthesizedunderpHI--4.Astheaminoacidligandsinthesecomplexesareintheirinnersaltformsandtheandnogroupsareprotonned,theycoordinatewithrareearthionsonlybyusingtheircarboxylgroups.Wehavenoticedthatthedeprotonizationoftheprotonnedaminogroupsisnecessarybeforethenitrogenatomsoftheaminogroupscancoordinatewiththemetalions.BycarefullyadjustingthePHvalueofasolutiontoabout5,wecrystalliz…  相似文献   

13.
结构新颖的双阴离子型桥联胺基胍基镱(Ⅲ)配合物{[Me2Si(NPh)2]2Yb[(NiPr)2CN(SiMe3)2]}{Li(THF)2}2是通过二胍基镱氯化物[(SiMe2)2NC(N'Pr)2]2Yb(μ-Cl)2Li(THF)2和桥联胺基锂盐PhLiNSiMe2NLiPh反应制得,该配合物经过了IR、元素分析和X-ray晶体结构的测定.该晶体为单斜晶系,P 21/c空间群,a=14.0001(8),b=17.6808(9),c=24.9565(16)A,B=95.994(3),V=6143.8(6)A3,Dc=1.287g/cm3,Z=4.  相似文献   

14.
<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   

15.
<正> INTRODUCTION. By mixing aqueous solutions of AgNO_3-Tu(mol ratio 1:1, Tu==SC(NH_2)2) with CuCI-Tu(mol ratio 1:3) we obtained a colourless crystalcompound. Its crystal and molecular structure was determined by X-raydiffraction and shortly reported in this paper.  相似文献   

16.
<正> W4S4 [S2P (OEt)2]6, Mr= 1974. 94, triclinic, P1, a = 14. 063 (5) , b = 16. 289(4), c= 13. 377(3) A ,α=92. 06 (2), β=95. 24(3), γ= 73. 06(2)°, V= 2919(3)A3,Z=2,DC=2. 18g/cm3, Moka radiation,λ =0. 71069A ,μ = 90. 64cm-1, F(000) = 1764,R=0. 053 and Rw = 0. 069 for 5422 reflections with I≥3σ(I).The title compound is comprised of a cubane-like cluster core [W4S4] in which every W atom is coordinated by six S atoms to form a distorted octahedron.  相似文献   

17.
<正> [Er(u-Met)(u-Gly)(H2O)4]2[Er(u-Met)2(HaO)4]2(ClO4)12(NMet=CH3S-(CH2)2CH(NH2)COOH,Gly=NH2CH2COOH), Mr=3194, trilinic, space group P1, a = 12.375(6),b= 14.041(13), c=19.074(13)A,α=80.85(6),β=80.72(6).γ=62.82(6)° ,Z=1,V= 2896A3,Dc=1.83 g/cm3,R=0.091. The carboxyl groups of Met and Gly in the title complex are bonded to Er atoms as bidentate bridging ligands.There are two different cations located at crystallographic symmetry centers in one unit cell.  相似文献   

18.
MgCl_2负载(dbm)_2Ti(OPh)_2催化乙烯聚合   总被引:4,自引:0,他引:4  
烯烃聚合的新型非茂催化剂由于合成相对简便并具有一些新特点,近年来开始受到人们的关注[1,2].IVB族金属的β二酮络合物与烷基铝或烷氧基铝形成的催化体系对烯烃聚合也显现出一定的聚合活性.在一定压力下,β二酮锆/MAO均相催化乙烯聚合时具有较高聚合活性[3].β二酮钛催化剂对于丙烯无规聚合和苯乙烯间规聚合均有较好结果[4~6].本文将报道用MgCl2负载的二苯氧基二(二苯甲酰甲烷)钛络合物((dbm)2Ti(OPh)2),以甲基铝氧烷(MAO)为助催化剂,常压催化乙烯聚合的结果.1 原料MgCl2为抚顺301厂产品.MAO(1.4mol/L甲…  相似文献   

19.
1INTRODUCTIoNFerrocenecontainingtransitionmeta1complexeshasarousedtheinterestofchemistsbecauseofitsnovelstructureandproperties"',Huangetal[2'3isynthesizedsomechainandbridgeformcomplexesandstudiedtheirIRandCV.Linetal[4isyn-thesizedthecrystalof[(dppf)PdCl,jO.5[(CH3),COj(dppf=1,11-(diphenylphosphine)-ferrocene)anddeterminedthestructurebyX-raydiffraction.Inthisarticlewereportthesynthesisandcrystalstructureof[(dppf),Pd,(ll)(p-Cl),j[PF,j2.2EXPERIMENTAL2.1PreparationAsolutionofO.86mm…  相似文献   

20.
1INTRODUCTIONFromreactionsof[RuCl,(PPh,),jwithcloso-[B,,H,,j'-respectivelyinEtOH/CH,Cl,t'i,CH,COOH/THF"'andC,H,COOH/CH,Cl,">solution,itcanbefoundthatbothalcoholandorganicacidcanreplacehydrogenatomsinborane.Further-more,accordingtotheirdifferentreactiontime(3h,1OOhand113hrespectively),wecanknowthatalcoholismoreactivetoreplacehydrogenatomsinborane.NowinordertoconfirmthisrulefurtherweusePhCH(OH)COOH/(CH3)2CHOHsolutioninsteadofabove-mentionedsolutions.Newcompounds(I)and(II…  相似文献   

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