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1.
溶剂性质对DBS/C~1~0H~2~1OH/溶剂体系的相行为 与结构的影响   总被引:1,自引:0,他引:1  
郭荣  于卫里  刘天晴  钱俊红 《化学学报》1998,56(12):1172-1179
在DBS/C~1~0H~2~1OH/溶剂体系中,以甲酰胺、水或甘油为溶剂时,在一定浓度范围内能生成O/W,W/O微乳液和层状液晶。C~1~0H~2~1OH在各种溶剂的DBS胶束中的分配系数K均很高。以甲酰胺、水为溶剂时,DBS能在一定浓度范围内生成层状液晶,但以甘油为溶剂时,则不能生成层状液晶。C~1~0H~2~1OH的加入有助于层状液晶的生成,但过量的C~1~0H~2~1OH却使层状液晶失稳。在相同质量比C~1~0H~2~1OH/DBS下,按顺序H~2O,FA,Gly,层状液晶中溶剂的渗透率α降低,d~0值亦降低;以FA为溶剂时,表示其表观有序度的Δν值却较高;以水为溶剂时,Δν值却较低;以Gly为溶剂时,Δν具有中等值。不同溶剂层状液晶两亲双层内的分子取向与溶剂性质对层状液晶稳定性的影响相一致。  相似文献   

2.
屈义彬  王镜明 《化学学报》1986,44(4):330-335
研究了各种条件下[Ir(NO)Cl~5]^-的电子光谱和红外光谱的变化,讨论了[Ir(NO)Cl~5]^-与[Ir(NO)~2Cl~5]^3^-之间的转化与平衡及[Ir(NO~2)Cl~5]^3^-的配位体交换反应.在稀盐酸溶液中[Ir(NO~2)Cl~5]^3^-有水合作用,由[Ir(NO~2)Cl~5]^3^-转变成[Ir(NO~2)(H~2O)Cl~4]^2^-的表观活化能E~a的平均值为107.5kJ/mol.  相似文献   

3.
本文阐述了用过硫酸铵/醋酸氨[ (NH~4)~2S~2O~8/HCOONH~4 ]和过硫酸铵/磷酸二氢钠·水[ (NH~4)~2S~2O~8/NaH~2PO~2·H~2O ]选择性还原1,1,3,4-四氯全氟丁烷CF~2ClCFClCF~2CFCl~2。介绍了应用这类选择性还原反应合成含氟吸入性麻醉剂CHF~2OCF~2CHClF (Enflurane)和CHF~2OCHClCF~3 (Isoflurane)。  相似文献   

4.
非水层状液晶的稳定性与相行为   总被引:3,自引:1,他引:3  
郭荣 《应用化学》1991,8(2):90-93
水体系层状液晶已研究较久,非水层状液晶则是近十年来才得到发展。本文以层状液晶的相行为和~2H NMR测量,研究并比较了非水层状液晶十二烷基硫酸钠/正癸醇溶剂以甘油或甲酰胺为溶剂时体系的结构与稳定性。 表面活性剂十二烷基硫酸钠(BDH,简写SDS)经无水乙醇重结晶两次提纯。用铂环法测  相似文献   

5.
以极性有机物为溶剂制备展状液晶已经引起重视,但关于极性有机溶剂对层状液晶结构和稳定性影响的研究还很不够.我们曾以~2H NMR测量研究了以甲酰胺代替甘油为溶剂,对非水层状液晶SDS/C_(10)H_(21)OH/溶剂体系稳定性的影响.本文则以小角X射线衍射测量,研究以甲酰胺代替甘油后,对层状液晶SDS/C_(21)H_(21)OH/溶剂体系结构的影响。  相似文献   

6.
水体系层状液晶已有较长的研究历史,非水层状液晶则是近年来才得发展.本文以层状液晶的相行为和~2H NMR测量,研究以极性有机物甘油代替水为溶剂后,对十二烷基硫酸钠/正癸醇/溶剂体系层状液晶稳定性的影响。1 实验试剂C_(12)H_(25)SO_4Na(SDS),正癸醇(C_(10)H_(21)OH,简为C_(10)OH),甘油(简为Gly)均同文献,水为二次蒸馏水.氚代物SDS_(-d25)和C_(10)OH_(-d21)均出自Cambridge Isotopes. 层状液晶单相区域的确定和~2H NMR测量见文献[92].  相似文献   

7.
合成了Fe[(Htrz)~9~/~4(NH~2trz)~3~/~4](BF~4)~2.H~2O(1)和Fe[(Htrz)~3~/~2(NH~2trz)](BF~4).3H~2O(2)两个"分子合金"类自旋转换配合物。其变温光谱表明,它们在室温附近具有自旋转换行为,同时还伴有热致变色及滞后现象。  相似文献   

8.
新型"分子合金"类Fe(II)配合物的合成和自旋转换性能   总被引:1,自引:0,他引:1  
合成了Fe[(Htrz)~9~/~4(NH~2trz)~3~/~4](BF~4)~2.H~2O(1)和Fe[(Htrz)~3~/~2(NH~2trz)](BF~4).3H~2O(2)两个"分子合金"类自旋转换配合物。其变温光谱表明,它们在室温附近具有自旋转换行为,同时还伴有热致变色及滞后现象。  相似文献   

9.
氯化稀土与丙氨酸配合行为的研究   总被引:10,自引:0,他引:10  
用半微量相平衡方法研究了SmCl~3-Ala-H~2O三元体系在25℃时的溶解度。结果表明体系中形成了两种配合物: Sm(Ala)~2Cl~3.3H~2O和Sm(Ala)~3Cl~3.3H~2O,合成了RE(Ala)~3Cl~3.3H~2O(RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy),RE(Ala)~2Cl~3.nH~2O(RE=La, Ce, Pr, Nd, Sm, n=3; RE=Ho, Yb,Y, n=4)与RE(AlA)Cl~3.6H~2O(RE=Eu, Gd,Tb, Dy, Ho, Yb, Y)二十四种固体配合物, 用化学分析、IR、UV、X射线分析及TG-DTG对配合物进行了表征, 发现了RECl~3与Ala形成配合物的规律性。  相似文献   

10.
由(NH~4)~2Mo~2S~12H~2O和(NH~4)(S~2CNC~4H~8)在PPh~3参与反应下,获得Mo~2S~4(S~2CNC~4H~8)~2化合物,对此二核钼簇合物进行了红外、电子光谱、电化学及单晶X射线结构表征,并尝试与多种金属化合物进行[2+1]反应,从反应产物的晶体结构分析发现了包括金属夺取端基S^2-形成Mo~2O~2S~2(S~2CNC~4H~8)~2化合物,Cu^+被氧化并夺取配体(S~2CNC~4H~8)^-形成Cu(S~2CNC~4H~8)~2以及Mo(V)还原为Mo(IV),S^2-氧化为(S~2)^2-而形成Mo~3(μ~3-S)(μ-S~2)~3[S~2CNC~4H~8]~3.  相似文献   

11.
Journal of Thermal Analysis and Calorimetry - Four ionic cobalt hexacyanidoferrate(II) complexes with formulae [Co(NH3)6]4[Fe(CN)6]3·12H2O (1) [Co(NH3)6]2Cl2[Fe(CN)6]·4H2O (2),...  相似文献   

12.
IntroductionPolyoxometalates constitute an enormous classof compounds whose unusual versatility and reac-tivity afford practical applications to many fields,such as catalysis,biology,medicine,and materialsciences[1— 4] .In recent years,hydrothermal tech-nique has become a vital tool in self- assemblychemistry.This technique,in combination with or-ganic templates,has been demonstrated to be wellsuited for the synthesis and the crystal growth ofpolyoxometalates with novel structures[5— 9] .Amo…  相似文献   

13.
层状液晶中KCl超微粒子的制备   总被引:8,自引:0,他引:8  
利用溶剂在层状液晶中的渗透性,和层状液晶中溶剂厚度的限定性,在TritonX-100/C10H21OH/H2O体系层状液晶中,以24.0%(质量分数)KCl水溶液代替组分水,制备水溶性超微粒子材料KCl,粒径大小约为4~6nm.  相似文献   

14.
郭荣  宋根萍  严鹏权  沈明 《化学学报》1997,55(10):937-942
将Pb(NO3)2和Ns2S分别溶于Triton X-100/C10H21OH/H2O体系层状液晶溶剂层中, 混和即可在溶剂层中生成PbS粒子, 并以层状液晶中溶剂层厚度的大小, 限定所合成PbS粒子的尺寸小于10nm, 改变有关组分含量对PbS超微粒子大小无显著影响, 所合成PbS超微粒子的平均粒径均小于10nm.  相似文献   

15.
In our efforts to construct new metal-organic frameworks (MOFs) by template-directing method, a new cadmium oxalate, [Co(NH3)6]2[Cd8(C2O4)11(H2O)4]·8H2O (denoted HNU-1), has been synthesized under hydrothermal condition in the presence of Co(NH3)6Cl3. The crystal structure of HNU-1 was determined by single-crystal X-ray diffraction (monoclinic, C2/c), a = 11.126(2)Å, b = 17.361(4)Å, c = 16.119(3)Å, β = 102.40(3)°, V = 3040.8(10)Å3 and Z = 8. The open framework of HNU-1 contains 12-ring channels and exhibits a 5-connected sqp topological network with dinuclear Cd(Ⅱ) clusters acting as nodes. The Co(NH3)63+ cations and unusual hydrogen-bonded (H2O)4 clusters are found in the 12-ring channels with an alternative arrangement. It is believed that the (H2O)4 clusters play a co-templating role in the crystallization of HNU-1.  相似文献   

16.
The FT IR and FT Raman spectra of Co(en)3Al3P4O16.3H2O (compound I) and [NH4]3[Co(NH3)6]3[Al2 (PO4)4]2.2H2O (compound II) are recorded and analysed based on the vibrations of Co(en)(3)3+, Co(NH3)(6)3+, NH4, Al-O-P, PO3, PO2 and H2O. The observed splitting of bands indicate that the site symmetry and correlation field effects are appreciable in both the compounds. In compound I, the overtone of CH2 deformation Fermi resonates with its symmetric stretching vibration. The NH4 ion in compound II is not free to rotate in the crystalline lattice. Hydrogen bonding of different groups is also discussed.  相似文献   

17.
The reaction of an S-bridged Co2(III)Ag3(I) pentanuclear complex, [Ag3[Co(aet)3]2][BF4]3 (aet = NH2CH2CH2S-), with paraformaldehyde in basic acetonitrile, followed by adding aqueous ammonia, produced an aza-capped Co2(III)-Ag3(I) complex, [Ag3[Co(L)]2]3+ ([1]3+) (L = N(CH2NHCH2CH2S-)3). The crystal structure of [1]3+ was determined by X-ray crystallography. [1][PF6]3 x H2O, empirical formula C18H44Ag3Co2F18N8OP3S6, crystallizes in the tetragonal space group 142m with a = 13.012(1) A, c = 24.707(2) A, and Z = 4. In [1]3+ the two aza-capped [Co(L)] units are linked by three Ag(I) atoms, such that the two Co(III) atoms are encapsulated in a macrobicyclic metallocage, [Ag3(I)(L)2]3-. [1]3+ was converted to an aza-capped Co4(III)Zn4(II) octanuclear complex, [Zn4O[Co(L)]4]6+ ([2]6+), by reaction with I- in the presence of Zn2+ and ZnO in water. The crystal structure of [2]6+ was also determined by X-ray crystallography. [2][PF6]6 x 8H2O, empirical formula C36H100Co4F36N16O9P6S12Zn4, crystallizes in the monoclinic space group P2(1/n) with a = 14.33(7) A, b = 25.67(10) A, c = 24.83(6) A, beta = 101.3(3) degrees , and Z = 4. In [2]6+ each of four [Co(L)] units is bound to each trigonal Zn3(II) face of the tetrahedral [Zn4(II)O]6+ core, such that each Co(III) atom is encapsulated in a macrobicyclic [Zn4(II)O(L)] fragment. Treatment of [2]6+ with a basic aqueous solution resulted in a cleavage of the Zn-S bonds to produce an aza-capped Co(III) mononuclear complex, [Co(L)] ([3]), from which [1]3+ is readily reproduced by the reaction with Ag+ in water. All the reactions were found to proceed with retention of the absolute configuration (delta or lambda) of the Co(III) chiral centers; deltadelta-[1]3+, deltadeltadeltadelta-[2]6+, and A-[3] were derived from deltadelta-[Ag3[Co(aet)3]2]3+. The contributions to circular dichroism (CD) from the triple helicity in [1]3+, besides from the asymmetric N and S donor atoms and the Co(III) chiral centers in [1]3+ and [2]6+, were estimated by comparing the CD spectra of deltadelta-[1]3+, deltadeltadeltadelta-[2]6+, and delta-[3].  相似文献   

18.
A new sandwich transition metal substituted polyoxotungstate, [NH3(CH2)4NH3]6[Co4(H2O)2(B-α-GeW9O34)2]}·7H2O 1, was hydrothermaUy synthesized and characterized by IR spectra and single-crystal X-ray diffraction. The single-crystal X-ray analysis reveals that the crystal crystallizes in monoclinic system, space group P21/c with a = 16.6073(6), b = 15.3333(5), c = 19.9869(7) A, β = 103.41(1)°, Mr = 5481.38, V = 4950.8(3) A3, Z = 2, Dc = 3.677 g/cm^3, F(000) = 4900, μ(MoKa) = 22.165 mm^-1, GOOF = 1.005, the final R = 0.0228 and wR = 0.0527. The crystal structure indicates that the [Co4(H2O)2(B-α-GeW9O34)2]^12- polyoxoanion contains two trivacant Keggin [B-α-GeW9O34]^10- fragments in a staggered fashion linked via a rhomb-like Co4O16 group in a centrosymmetric arrangement (C2h symmetry) leading to a sandwich-type structure.  相似文献   

19.
[Co3(1,2-S2C6H4)3(PPh3)3][CoBr3(DMF)].sol (1, sol=CHCl3,O(C2H5)2,H2O) was obtained from the reaction of CoBr(PPh3)3 with Na2(S2C6H4) in chloroform. The Co3 core in the cation of 1 exhibits a metal-metal bonded isosceles triangle, in which the two longer Co-Co bonds are both bridged by S2C6H4 ligands on two sides of the triangle plane respectively, while the bottom short Co-Co bond is bridged by the third bidentate S2C6H4 ligand. A series of polynu-clear cobalt cluster compounds with phosphine, thiolate and/or sulphur ligands were prepared by low oxidation state Co+ with thiolates in organic solvents. These tri-, tetra-, hexa-, heptanuclear cluster compounds 1-8 with various types of crystal structures can be viewed as the condensed polynuclear cobalt complexes that the cobalt atom frameworks with sulphur bridged were built through the small triangular units of [Co3S3nL3] (n=1,2) with or without [CoL] (L=PR3, Br, Cl, 5-C5H5) fragments.  相似文献   

20.
The reaction of [Mo3S4(H2O)9]4+ (1) with hydrotris(pyrazolyl)borate (Tp) ligands produced [Mo3S4Tp3]Cl x 4 H2O ([3]Cl x 4 H2O) in an excellent yield. An X-ray structure analysis of [3]Cl x 4 H2O revealed that each molybdenum atom bonded to the Tp ligand. We report four salts of 3, [3]Cl x 4 H2O, [3]tof x 2 H2O, [3]PF6 x H2O, and [3]BF4 x 2 H2O in this paper. The solubility and stability of the chloride salt in organic solvents differ completely from those of the other salts. We have also prepared a new compound, [Mo3OS3Tp3]PF6 x H2O ([4]PF6 x H2O), via the reaction of [Mo3OS3(H2O)9]4+ (2) with KTp in the presence of NH4PF6. All the molybdenum atoms bonded to Tp ligand. 1H NMR signals corresponding to nine protons bonded to three pyrazole rings in one Tp were observed in a spectrum (at 253 K) of [3]BF4 x 2 H2O. It shows that cluster 3 has a 3-fold rotation axis in CD2Cl2 solution. Twenty-one 1H NMR signals corresponding to twenty-seven protons bonded to nine pyrazole rings in three Tp ligands were observed in a spectrum (at 233 K) of [4]PF6 x H2O; obviously, 4 has no 3-fold rotation axis, in contrast to 3. The short CH...mu3S distance caused large upfield chemical shifts in the 1H NMR spectra of 3 and 4. The reaction of 3 with metallic iron in CH2Cl2 produced [Mo3FeS4XTp3] (X = Cl (5), Br (6)). X-ray structure analysis of 5 has revealed the existence of a cubane-type core Mo3FeS4. Complex 3 functions as a metal-complex ligand for preparing a novel mixed-metal complex even in nonaqueous solvents. The cyclic voltammogram of 5 shows two reversible one-electron couples (E(1/2) = -1.40 and 0.52 V vs SCE) and two irreversible one-electron oxidation processes (E(pc) = 1.54 and 1.66 V vs SCE).  相似文献   

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