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1.
<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   

2.
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   

3.
<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   

4.
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   

5.
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   

6.
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   

7.
通过水热合成的方法,以1,4-环己烷二羧酸、2,4-二氨基-6-甲基三嗪和CdCl_2·2.5H_2O为原料合成了一种单核的化合物{Cd(dmt)_2(Hchdc)_2(H_2O)_2}_n(dmt=2,4-diamino-6-methyl-triazine,H2chdc=1,4-cyclohexanedicarboxylic acid),并进行了IR和X射线单晶衍射(常温)的分析.结果表明,该化合物属于P2/c空间群,单斜晶系,晶胞参数:a=1.330 26(11)nm,b=0.541 47(4)nm,c=2.415 54(16)nm,β=115.751(3)°,V=1.567 1(2)nm~3,Z=2,Dc=1.570g/cm~3,F(000)=764,R1=0.035 2,wR2=0.092 7.该化合物中,中心金属离子Cd(II)与氧相连形成六配位构型,并通过4种不同的氢键作用最终形成了三维的堆积结构.  相似文献   

8.
1 INTRODUCTION The synthesis of new organic-inorganic hybrid compounds is a relatively new research area that has developed rapidly in the last several years[1]. Bische- late ligand[2, 3], such as azobis(2-pyridine), is a novel tetradentate ligand expect…  相似文献   

9.
将MnCO3 与2,4,6-三硝基间苯二酚(斯蒂芬酸、TNR)分散于蒸馏水中, 加热搅拌制备出斯蒂酚酸锰溶液,再与碳酰肼(CHZ)水溶液反应制备〔Mn2 (TNR)2(CHZ)2(H2O)4〕·2H2O(C14H26Mn2N14O24, Mr= 884.36),并对其进行了元素分析和红外表征,利用单晶分析测定了晶体结构。该化合物为双核配合物,属三斜晶系,空间群为P1,晶体学数据如下:a= 7.280(1),b= 10.318(1),c= 11.106(1),α= 94.56(1),β= 91.86(1),γ= 106.88(1)°,V= 794.4(2)3,Z= 1,Dc= 1.849g.cm - 3, μ=9.15cm - 1, F(000)= 450, I> 2σ(I)的独立可观测点个数为2783,最终偏离因子R=0.0272, Rw = 0.0639。分子为中心对称,配位多面体为略有畸变的五角双锥体构型。  相似文献   

10.
<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   

11.
本文合成了数个以有机磷作桥基配位体的同核钴和异核铁钴原子簇羰基化合物.通过元素分析、IR谱和~1H-NMR谱测定,确定三核钴簇合物Co_5(CO)_9-(μ_3-PR)和异核铁钴簇合物Co_2Fe(CO)_9(μ_3-PR)的分子骨架Co_3P和Co_2FeP具有三角锥构型,而四核钴簇合物Co_4(μ-CO)_2(CO)_8(μ_4-PR)_2的分子骨架Co_4P_2为八面体构型.  相似文献   

12.
<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   

13.
<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   

14.
1 INTRODUCTION At present, the polyaluminium compounds are mainly studied by single-crystal X-ray diffraction method to obtain the components, structures and exis- tence forms of aluminium in hydrolysis system, and then hydrolysis courses and mechanisms of each hydrolytic polyaluminium cation could be further dis- closed[1~5]. Generally, the single crystals suitable for X-ray diffraction are obtained from the crystallization of polyaluminium cations into sulfates or selenates. Following …  相似文献   

15.
1INTRODUCTION There is currently considerable interest in the ra-tional design and controlled synthesis of metal-organic frameworks(MOFs)with unique structural motif on account of their promising applications as catalysts,gas storage,selective separation,sensor,ion exchange and magnetic materials[1,2].Particu-larly,the supramolecular architectures with helical structures have received much more attention over the past decades owing to their specific functions in biology.It is well recogn…  相似文献   

16.
本文用CNDO/2方法研究了(dmpe)_2H_tCrBH_4(Ⅰ)、(dmpe)_2H_tCrAlH_4(Ⅱ)和[(dmpe)_2H_tCrAlH_4]_2(Ⅲ)(dmpe=(CH_3)_2PCH_2CH_2P(CH_3)_2,在计算时,我们用二个PH_3代替一个(dmpe)的电子结构。结果表明:(1)在(Ⅱ)的6b_1(HOMO),7a_1占据轨道中,Cr3d轨道与2H_b1S轨道(H_b为桥氢原子)对称性不匹配,相互排斥,而在(Ⅰ)中这种排斥有所减弱;Cr(u-H_b)_2Al骨架较Cr(u-H_b)_2B能量高而不稳定。(2)在(Ⅲ)的电子结构中Cr3d与2H_b1S之间排斥大为减弱,Cr(u-H_b)_2Al稳定性提高;新形成的AL(u-H)_2AL能量较低;在较高占据轨道中H_t和H_b成份多,活泼性强,这可能是H_t和H_b易交换的主要原因。三个化合物在电子结构上的差异较合理解释了实验现象。  相似文献   

17.
<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   

18.
<正> (Ph2Ppy)2(μ-Cl)2Cu2Cl2 (C34H28Cl4Cu2N2P2): Mr=795.5, triclinic, Pl, a=13.891(2), b= 13.196(3), c= 20.158(4) A, d= 90.28(1)°, β=110.05(2)°, r= 90.13(1)°, Z=4, V= 3471.04A3, Dx=1.53 gcm-3, R=0.066, Rw= 0.076 for 5486 observed unique reflections. The complex was prepared by the reaction of (Ph2Ppy)2NiCl2 with CuC≡CPh in CH2Cl2 solution.  相似文献   

19.
1 INTRODUCTION The development of supramolecular complexes has recently attracted considerable attention due to the fundamental interest in self-assembly processes of transition-metal complexes, supramolecular che- mistry and crystal engineering[1]. The ultimate goal is to gain control in order to direct their function[2]. Self-assembly through coordination and nonco- valent interactions such as hydrogen bonds, aromatic π···π stacking, steric repulsion and Van der Waals forces leads …  相似文献   

20.
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