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2.
The molecular and crystal structures of N≡C-C6H4-C6H4-O-(CH2)8-O-CO-CH=CH2 (4(3-acryloyloxy)octyloxy-4′-cyanobiphenyl) (I) and N≡C-C6H4-C6H4-O-(CH2)6-O-CO-CH=CH2 (4(3-acryloyloxy)hexyloxy-4′-cyanobiphenyl) (II) were determined by X-ray diffraction. The structures of I and II are stereotype. The space group of I and II is C2/c, Z = 8; lattice parameters I: a = 34.677(7)?, b = 9.452(2)?, c = 13.004(3) ?, β = 99.30(3)°; II: a = 30.858(6) ?, b = 9.504(2) ?, c = 13.082(2) ?, β = 92.78(3)°. The planar extended molecules I and II are packed in the unit cell to give clearly differentiated aliphatic and aromatic regions throughout the whole crystal. All intermolecular contacts are concentrated in the aromatic region. The molecular packing is very loose but the aromatic areas of I and II fully coincide. The only free parameter of the structure is the length of the aliphatic chain (CH2)n (n = 8 and 6). According to DSC data, compound I possesses enantiotropic mesomorphism and II possesses monotropic mesomorphism.  相似文献   

3.
金属簇合物具有独特的结构和成键方式。本文对铑簇合物的简正振动分析进行了研究。通过红外光谱用石蜡油糊涂KBr和聚乙烯窗口, 在Nicolet 200SXV FT-IR光谱上测定了Rh2(CO)4(μ-Cl)2的构型, 并使用分子振动全分析程序MVTA(Basic语言), 在PC机上进行计算。  相似文献   

4.
The cation distribution among the two crystallographic cation sites of the Cr3S4 structure was determined in VTi2Se4 and VCr2Se4 by high-resolution neutron diffraction, using Rietveld analysis. The results showed a considerable disorder but they nevertheless revealed the site preference of V atoms for the 2(a) site in both compounds. The compositional changes of the lattice parameters and the transition temperatures to the CdI2-type structure in (VxTi1−x)3Se4 and (CrxV1−x)3Se4 were compared with those in (CrxTi1−x)3Se4 and (FexCr1−x)3Se4, and discussed from the viewpoint of the site preference of the cation.  相似文献   

5.
Tetrakis(di-tert-butylmethylsilyl)tetragermacyclobutadiene]ruthenium tricarbonyl [η4-(But 2MeSi)4Ge4]Ru(CO)3 is synthesized. This analogue of well-known cyclobutadiene transition metal complexes bears a tetragermacyclobutadiene derivative as ligand. The structure and spectroscopic parameters of the complex are compared with those of its iron-containing analogue [η4-(But 2MeSi)4Ge4]Fe(CO)3. Based on experimental data and results of quantum chemical calculations, it is shown that the π-donating ability of ligands increases upon replacement of carbon atoms in the cyclobutadiene moiety by silicon or germanium atoms, tetrasilacyclobutadiene and tetragermacyclobutadiene being comparable in π-donating activity.  相似文献   

6.
用HP5988A型色谱-质谱仪的多离子选择检测器和310工程计算机系统考察了PtCl_(2-)(PPh_3)_2,Pt-3(CO)_3(PPh_3)_4和Pt_4(CO)_5(PPh_3)_4等化合物在γ-Al_2O_3,TiO_2和SiO_2载体上的程序升温热分解特性。结果表明:铂簇合物在TPDE-H_2下的脱羰基过程比TPDE-He下简单。在TPDE-H_2下,在373K能检测到单一的CO_2脱附峰,三苯基膦配体在不同载体上的分解和脱附时,苯是主要脱附产物(≥90mol%);在TPDE-He下,三苯基膦配体的分解和脱附特性同载体性质明显有关。若以脱附苯的mol%为指标,则TiO_2>γ-Al_2O_3>SiO_2。另外,在两种情况下,三苯基膦配体的分解和脱附,均因铂的存在而加速。在脱附产物中,均未发现任何含磷化合物,证明磷在铂簇合物分解后还残留在催化剂上。  相似文献   

7.
《Polyhedron》2001,20(9-10):915-922
The interaction of the individual M4(acac)43-OMe)4(MeOH)4 complexes, M=Co, Ni in toluene/methanol media provided crystals of (Co,Ni)4(acac)43-OMe)4(MeOH)4 (I) — the product of co-crystallization of isomorphous products. The oxidation of a MeOH solution of I in air in the presence of NaOAc and aminoalcohols as catalysts gave Co2Ni2(acac)43-OMe)4(OAc)2 (II), an individual heterometallic derivative. The interaction of Mg(OCH(CH3)CH2NMe2)2 with Cu(acac)2 in toluene/methanol media produced Mg4(acac)43-OMe)4(MeOH)4 (III) as the only isolatable product. The starting Co and Ni homometallic complexes as well as the heterometallic CoNi complex II were used to prepare the zeolite-supported oxide catalysts which exhibited extremely high activity towards methanol oxidation.  相似文献   

8.
以有机分子乙二胺作为模板剂合成了新型磷酸钒孔道化合物(H3NCH2CH2NH3)3^-[(VO)4(PO4)2(HPO4)4,并通过X射线单晶衍射实验进行了结构表征,晶体学数据为:C2/c,a=1.8505(9)nm,b=0.7089(4)nm,c=2.3304(10)nm,β=96.43(3)°,V-3.038(3)nm^3,Z=8,R=0.067,Rw^b=0.1635,该化合物具有非常独特和规整的二维孔道骨架结构,进一步的晶体化学研究表明该化合物为一新的VPO物相。  相似文献   

9.
以有机分子乙二胺作为模板剂合成了新型磷酸钒孔道化合物(H3NCH2CH2NH3)3^-[(VO)4(PO4)2(HPO4)4,并通过X射线单晶衍射实验进行了结构表征,晶体学数据为:C2/c,a=1.8505(9)nm,b=0.7089(4)nm,c=2.3304(10)nm,β=96.43(3)°,V-3.038(3)nm^3,Z=8,R=0.067,Rw^b=0.1635,该化合物具有非常独特和规整的二维孔道骨架结构,进一步的晶体化学研究表明该化合物为一新的VPO物相。  相似文献   

10.
The i.r. and Raman spectra of room temperature phase (phase II) of (NH4)3H(SO4)2 and (ND4)3D(SO4)2 as polycrystalline samples and single crystals have been investigated between 4000 and 30 cm−1. An assignment of internal and external modes is given in terms of group frequencies and symmetry types. This crystal contains non-centrosymmetric dimers (SO4HSO4)3− where sulphate ions are associated by strong asymmetric OH … O hydrogen bonds; they are characterized by two strong Raman bands at 1078 and 966 cm−1, and a νOH frequency at about 1250 cm−1. The acidic proton is statistically disordered around the crystallographic symmetry centre while all of the NH+4 ions show an important dynamical orientational disorder.  相似文献   

11.
1 INTRODUCTION Recent years have seen a drastic increase of compounds containing the Mo3S4 core. A major synthetic route to these compounds is by the reaction of the aqua ion [Mo3S4(H2O)9]4+ with different kinds of ligands replacing some or all of the water molecules. In this way, Mo3S4(dtp)4(H2O), which was synthesized by the spontaneous- assembly method in 1986[1] and its structural characterization and chemical reactivity have been well recognized [2], can be rationally synthesize…  相似文献   

12.
林观阳  卫革成 《结构化学》1992,11(3):200-203
标题化合物SmCl_3(THF)_4(M_r=545.2)晶体属正交晶系,空间群为Pdd 2。晶胞参数为a=9.211(4),6=16.436(6),c=29.666(12);V=4491(3) ~3;Z=8,D_c=1.61g.cm~(-3),F(000)=2184,μ_c=30.3cm~(-1)。最终的偏因子R=0.063,R_(to)=0.062。Sm~(3+)与三个Cl~-及四个四氢呋喃分子中氧原子配位,形成一个五角双锥的空间结构,其中二个氯原子分别位于二个顶点位置。分子中有一个通过Sm~(3+)及Cl~-的C_2轴。Sm-Cl及Sm-0的平均键长分别为2.683(5)及2.469(11)。  相似文献   

13.
在分子水平上,研究担载过渡金属簇羰基络合物在担载及活化时的结构变化过程,不但有助于系统了解固载的过渡金属簇羰基络合物的表面金属有机化学,还可以获得制备高分散金属簇催化剂的信息.目前研究比较多的担载过渡金属簇羰基络合物是Fe,Os,Rh等络合物,对Pt簇络合物的研究比较少.其中Ichikawa研究了担载的[Pt_3(CO)_6]_n·NEt_4(n=1—5)的红外光谱和络合物分解后CO的吸附态及金属分散度.  相似文献   

14.
测定了三元体系La(ClO4)3-OCBAAP-H2O在30℃时的溶解度.结果表明,该体系有一个新固相(不一致溶解化合物)La(OCBAAP)4(ClO4)3·6H2O形成.参考该体系溶度图确定合成条件,合成了系列化合物Ln(OCBAAP)4(ClO4)3·nH2O(Ln=La,n=6;Ln=Pr,Nd,Sm,Gd,Yb,n=2).通过化学分析、元素分析、TG-DTG、IR和密度对化合物进行了表征,计算了La(OCBAAP)4(ClO4)3热分解过程各阶段的表观活化能.  相似文献   

15.
Abstract

[Cu(O2CCH3)2]2, 1, reacts with pyridine to form violet-blue Cu(O2CCH3)2(pyridine)3, 2, in > 90% yield. 2 crystallizes from pyridine with a distorted square-pyramidal geometry around copper with the monodentate acetate ligands located diagonally in the basal positions. 1 reacts with Bi(OCMe3)3 in THF to form blue Cu6(μ-O2CCH3)44-O2CCH3)2(μ-OCMe3)6, 3. 3 crystallizes from THF/hexanes with a hexagon of copper atoms linked by six doubly-bridging tert-butoxide ligands, four doubly-bridging bidentate acetates, and two quadruply-bridging bidentate acetate ligands.  相似文献   

16.
用将s电子和p电子分开处理的“CNDO”法,计算了HCo(CO)_4及HCo(CO)_3(PH_3)的电子结构。计算结果关联了许多实验事实。这方法可用于过渡金属络合物的研究。  相似文献   

17.
Russian Journal of Electrochemistry - Composites of (1 – x)Al2(WO4)3–xWO3 and (1 – x)Al2(WO4)3–xAl2O3 are synthesized and their conductivity is studied as dependent on the...  相似文献   

18.
CrystalStructureof[La(NO_3)_3(12-crown-4)-(H_2O)](12-crown-4)MaoJiang-Gao;JinZhong-Sheng;YuFeng-Lan(LaboratoryofRareEarthChemi?..  相似文献   

19.
通过 (η5 C5H5) 2 Fe2 (CO) 4和硒粉在沸腾的甲苯中反应可制得含 μ3 Se的立方烷簇合物 (η5 C5H5) 4Fe4 (μ3 Se) 4(1) ,而由 (η5 RC5H4 ) 2 Cr2 (CO) 4S在甲苯中回流可制得含 μ3 S的立方烷簇合物 (η5 RC5H4 ) 4Cr4 (μ3 S) 4(2 ,R =COMe ;3,R =CO2 Me)。企图通过 (η5 EtO2 CC5H4 ) 2 Fe2 (CO) 4(5 )和硫黄制备 μ3 S立方烷簇合物 (η5 EtO2 CC5H4 ) 4Fe4 (μ3 S) 4(6 )未获成功 ,其中 5是由 η5 EtO2 CC5H4 Fe(CO) 2 Na与 η5 EtO2 CC5H4 Fe(CO) 2 I (4 )缩合制得。新化合物 1~ 5经元素分析 ,IR和1 HNMR光谱表征  相似文献   

20.
(η6-Arene)Nd(AlCl4)3-AIR3催化丁二烯的聚合   总被引:1,自引:0,他引:1  
关于η~6-芳烃过渡金属有机络合物催化烯烃聚合的研究已早有报道.但对于η~6-芳烃稀土络合物催化烯烃聚合的研究至今未见报道.我们在研究了(η~6-C_6H_6)Nd-(AlCl_4)_3-AlR_3催化异成二烯聚合的基础上,又考察了不同芳烃烯土络合物和几种AlR_3组成的催化剂对丁二烯聚合的催化活性. 1.原料及试剂:丁二烯和烷基铝均为聚合级.汽油分别经浓硫酸,氢氧化钠水溶  相似文献   

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