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1.
自从Roper等人在1979年合成了第一个锇的甲醛配合物Os(η~2-CH_2O)(CO)_2(PPh_3)_2以来,Fe、Ir、V等过渡金属配合物与甲醛反应的研究结果相继报道.这些工作对研究一氧化碳的加氢机理有着十分重要的意义.甲醛的氢甲酰化合成乙二醇在C_1化学中是一个值得开展的研究课题.因此,甲醛在过渡金属配合物上反应性质的研究与寻找有效的甲醛氢甲酰化催化剂密切相关. Misono等人在1968年报道过甲醛与HCoN_2(PPh_3)_3(1)发生了脱羰基反应,得到钴的  相似文献   

2.
余秀芬  蒋亚琪 《化学学报》1992,50(7):649-653
本文应用醋酸铬(Ⅱ)在吡啶溶液中置换[Fe~2MO(CH~3CO~2)~6(H~2O)~3]·nH~2O(M=Mn,Co,Ni)中三价铁离子的反应,制备了三个标题化合物.从测定的晶胞参数可以确定它们为异质同晶,进而测定其中[FeCrCoO(CH~3CO~2)~6Py~3]·Py三核物的晶体结构.晶体属三方晶系,a=1.7516,c=1.1027nm,V=2.9297nm^3,Z=3,空间群R32.同时还研究了三个标题化合物吡啶溶液的民电子光谱,应用配位场理论对有关金属离子的d-d跃迁谱带进行归属和配位场参数的计算.  相似文献   

3.
合成邻香兰素(2-羟基-3-甲氧基苯甲醛)与α-萘胺Schiff碱硝酸稀土配合物[LnL_2(NO_3)_2NO_3(Ln:镧系元素,L:Schiff碱配体)。配合物由一个中心稀土离子,两个Schiff碱和三个硝酸根组成,两个Schiff碱都是氮、氧双配位,两个硝酸根是双齿配位,另一硝酸根在配合物外界。中心稀土离子是八配位的,满足稀土八配位的稳定结构。  相似文献   

4.
5.
不同温度下LaAlO3 : Eu的光谱分析   总被引:4,自引:0,他引:4  
范英芳  杨频  潘大丰 《化学学报》1997,55(9):872-879
本文基于双层点电荷配位场(DSCPCF)模型, 计算分析了77K, 300K和500K温度下Eu^3^+离子在LaAlO3中的配位场微扰能级及其光谱行为, 结果与实验吻合较好。由于随着温度的升高,Eu^3^+点的对称性发生变化(D3→Oh), 而使计算参数的取值有微小差别, 计算得到的配位场参数也有规律性的变化, 尤其是500K时B0^2值变号, 使计算的DSCPCF能级次序稍不同于其它两个温度。  相似文献   

6.
甲基丙烯酸丁酯(BMA)在2-乙基己酸钕[Nd(Oct)_3]和三异丁基铝[Al(i-Bu)_3]配合催化下的聚合反应结果表明。以正己烷和石油醚为溶剂的聚合转化率高于甲苯和四氢呋喃体系。4种不同配体的钕盐的聚合转化率差别不大。但是,以Nd(Oet)_3-Al(i-Bu)_3为催化剂时聚甲基丙烯酸丁酯的分子量最高。聚合反应速度与单体浓度和催化剂浓度均成一次方关系。甲基丙烯酸丁酯的聚合反应活化能为47.40kJ/mol。  相似文献   

7.
合成邻香兰素(2-羟基-3-甲氧基苯甲醛)与α-萘胺Schiff碱硝酸稀土配合物[LnL~2(NO~3)~2]NO~3(Ln: 镧系元素, L: Schiff碱配体)。配合物由一个中心稀土离子, 两个Schiff碱和三个硝酸根组成, 两个Schiff碱都是氮、氧双配位, 两个硝酸根是双齿配位, 另一硝酸根在配合物外界。中心稀土离子是八配位的, 满足稀土八配位的稳定结构。  相似文献   

8.
9.
本文应用醋酸铬(Ⅱ)在吡啶溶液中置换[Fe~2MO(CH~3CO~2)~6(H~2O)~3]·nH~2O(M=Mn,Co,Ni)中三价铁离子的反应,制备了三个标题化合物.从测定的晶胞参数可以确定它们为异质同晶,进而测定其中[FeCrCoO(CH~3CO~2)~6Py~3]·Py三核物的晶体结构.晶体属三方晶系,a=1.7516,c=1.1027nm,V=2.9297nm^3,Z=3,空间群R32.同时还研究了三个标题化合物吡啶溶液的民电子光谱,应用配位场理论对有关金属离子的d-d跃迁谱带进行归属和配位场参数的计算.  相似文献   

10.
用凝胶法合成了标题配合物,并进行了元素分析、红外光谱、质谱及差热-热重等物性表征;用四圆衍射仪测定了它的晶体结构。晶体属三斜晶系、空间群P1,晶胞参数α=9.097(2),ι=15.754(3),(?)=16.556(2),(?)=88.08(1)°,(?)=81.29(1)°,(?)=86.62(2)°Z=2。结构分析表明,该配合物中冠醚与铵离子形成配阳离子;铋(Ⅲ)由硫氰酸根和氯离子配位,并以配体桥联形成链状聚合的配合阴离子,配合阴、阳离子主要以静电吸引形成配合物。  相似文献   

11.
层状液晶中水溶性超微粒子材料[Co(NH~3)~6]Cl~3的制备   总被引:2,自引:0,他引:2  
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/C~10H~21OH/H~2O体系层状液晶中, 以4%Co(NH~3)~6]Cl~3水溶液组分水制备水溶性超微粒子材料[Co(NH~3)~6]Cl~3, 粒径约为3~6nm。  相似文献   

12.
Preparation and Crystal Structure of (NH4)2[V(NH3)Cl5]. The Crystal Chemistry of the Compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2, and M2VXCl5 with M = K, NH4, Rb, Cs and X ? Cl, O (NH4)2[V(NH3)Cl5] crystallizes like [Rh(NH3)5Cl]Cl2 in the orthorhombic space group Pnma with Z = 4. The compounds are built up by isolated NH4+ or Cl? and complex MX5Y ions. The following distances have been observed: V? N: 213.8, V? Cl: 235.8–239.1, Rh? N: 207.1–208.5, Rh? Cl: 235.5 pm. Both structures differ from the K2PtCl6 type mainly in the ordering of the MX5Y polyhedra. The compounds M2VCl6 and M2VOCl5 with M = K, NH4, Rb, and Cs crystallize with exception of the orthorhombic K2VOCl5 in the K2PtCl6 type. The ordering of the MX5Y polyhedra in the compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2 and K2VOCl5 enables a closer packing.  相似文献   

13.
It is shown that nanopores are formed during desorption of NH3 from Mg(NH3)6Cl2, which has been proposed as a hydrogen storage material. The system of nanopores facilitates the transport of desorbed ammonia away from the interior of large volumes of compacted storage material. DFT calculations show that there exists a continuous path from the initial Mg(NH3)6Cl2 material to MgCl2 that does not involve large-scale material transport. Accordingly, ammonia desorption from this system is facile.  相似文献   

14.
Isopiestic measurements have been carried out at 298.15 K for the quaternary aqueous solution H2O+KCl(sat)+NaCl+NH4Cl saturated with potassium chloride and its ternary sub systems H2O+KCl (sat)+NaCl and H2O+KCl(sat)+NH4Cl. Taking sodium chloride (aq) or calcium chloride (aq) as reference solutions, osm otic coefficients and water activities of the aqueous solution were determined. The experiment results show that the isopiestic actions of the quaternary system related to its ternary sub-systems are in excellent agreement with the ideal like solution model.  相似文献   

15.
Russian Journal of General Chemistry - The reaction of [Pt(NH3)4]Cl2 with NH4VO3 in alkaline solution in an autoclave at 190°C was studied. The solid autoclave thermolysis product was...  相似文献   

16.
We present here both an ab initio and quantum mechanical/molecular mechanical (QM/MM) study of the cis-[Pt(NH3)2Cl4] complex reduction by methyl thiolate anion, SCH(-3), which is used as a model of glutathione. Geometry and electronic structure of cis-[Pt(NH3)2Cl4] are determined without and in aqueous medium. The mechanism of the reaction of reduction is characterized. The calculated activation energy of the reaction compares remarkably well with the experimental value.  相似文献   

17.
We analyzed the molecular orbitals for a Al(4)Cl(4)(NH(3))(4) compound, which is a model of the (AlBr x NEt(3))(4) crystal structure recently reported by Schn?ckel and co-workers. We found that even though Al(4)Cl(4)(NH(3))(4) contains a planar square Al(4) cluster it is not an aromatic compound. However, the addition of two sodium atoms to Al(4)Cl(4)(NH(3))(4) yields a new Na(2)Al(4)Cl(4)(NH(3))(4) compound which is a pi-aromatic molecule. We hope that prediction of this new compound will facilitate a synthesis of aluminum aromatic solids.  相似文献   

18.
One metastable linkage nitrosyl isomer can be generated in [Pt(NH(3))(4)Cl(NO)]Cl(2) by irradiation with light in the red spectral range. The potential energy barrier for the thermal relaxation of the metastable state to the ground state has an amount of E(A) = (0.27 +/- 0.03) eV. The decay follows the Arrhenius law and E(A) is independent of temperature. At room temperature the metastable state has a lifetime of tau = 3.8 x 10(-5) s after generation by pulsed laser illumination. Below T = 100 K about 30% linkage NO isomers can be generated in a powder sample by irradiation with lambda = 658 nm. DFT calculations demonstrate the rotation of the NO ligand from Pt-N-O to Pt-O-N as a unique linkage isomer. Consequently, only one new nu(NO) stretching vibration is detected with a shift from 1673 cm(-1) to 1793 cm(-1) by 120 cm(-1), to higher frequencies in good agreement with the DFT calculations. In the metastable state new electronic absorption bands are observed in the blue-green and near infrared spectral range. The metastable state can be optically accessed via a (5d + pi(NO)) -->pi*(NO) transition. [Pt(NH(3))(4)Cl(NO)]Cl(2) is diamagnetic with a Pt(5d(8)) configuration and thus represents the first {MNO}(8) complex with experimental evidence for a light-induced nitrosyl linkage isomer.  相似文献   

19.
The Ru(II) complex fac-[RuCl(dmso-S)(3)(dmso-O)(2)][PF(6)] (P2) was found to be an excellent precursor for the facile preparation in high yield of half sandwich-type compounds of the general formula fac-[RuCl(dmso-S)(3)(N)(2)][PF(6)] (e.g. (N)(2) = 1,2-diaminoethane (en, 4), trans-1,2-diaminocyclohexane (dach, 5), or 2 NH(3) (6)). Neutral half sandwich-type compounds of the general formula fac-[RuCl(dmso-S)(3)(N-O)] where N-O is an anionic chelating ligand (e.g. N-O = picolinate (pic, 7)) are best prepared from the universal Ru(II)-dmso precursor cis-[RuCl(2)(dmso)(4)] (P1). These complexes, that were fully characterized in solution and in the solid state, are structurally similar to the anticancer organometallic compounds [Ru(η(6)-arene)(chel)Cl][PF(6)](n) but, in place of a face-capping arene, have the fac-Ru(dmso-S)(3) fragment. In contrast to what observed for the corresponding arene compounds, that rapidly hydrolyze the Cl ligand upon dissolution in water, compounds 4-6 are very stable and inert in aqueous solution. Probably their inertness is the reason why they showed no significant cytotoxicity against the MDA-MB-231 cancer cell line.  相似文献   

20.
The structure of N,N-dimethylethylenediammonium pentachloroantimonate(III), [(CH3)2NH(CH2)2NH3][SbCl5], NNDP, was investigated at 100 and 15 K at ambient pressure, as well as at pressures up to 4.00 GPa at room temperature in the diamond-anvil cell. The stable structure at low temperatures and low pressures consists of isolated [SbCl5]2- anions and [(CH3)2NH(CH2)2NH3]2+ cations. The inorganic anions have a distorted square pyramidal geometry. They are arranged in linear chains parallel to the c axis. In contrast to the low-temperature studies, where no phase transition was detected, pressure induces a P2(1)/c --> P2(1)/n phase transition between 0.55 and 1.00 GPa, accompanied by a doubling of the a unit-cell parameter. This solid-solid transition results from changes in the electron configuration of the Sb(III) atom and formation of the Sb-Cl bridging bonds between inorganic polyhedra to form, at approximately 1.0 GPa, isolated [Sb2Cl10]4- units consisting of [SbCl6]3- octahedra and [SbCl5]2- square pyramids connected by a common corner. The intermolecular distances continuously decrease with further increase in pressure, and at approximately 3.1 GPa, zigzag [{SbCl5}n]2n- chains containing corner-sharing [SbCl6]3- octahedra are formed. The unit-cell volume of NNDP decreases by 18.15% between room pressure and 4.00 GPa. The linear distortions of the [SbCl5]2- and [SbCl6]3- polyhedra decrease with increasing pressure and decreasing temperature and indicate a reduction in the stereochemical activity of the lone electron pair on the Sb(III) atom.  相似文献   

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