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1.
《物理化学学报》1999,15(6):6-31G
用密度泛函理论UB3LYP/6-31G(d,p)方法研究了二甲胺自由基(CH  相似文献   

2.
Novel anhydrous trinuclear 3-oxo complexes of Cr(III), Cr3(3-O)(CF3COO)6(CH3COOH)2(CF3COO) (I) and of Cr(III,III,II), Cr3(3-O)(CF3COO)6(CH3COOH)2(THF) (II) (where THF is (CH2)4O) are synthesized by anodic dissolution of metallic chromium in solutions of trifluoroacetic acid in acetonitrile and in tetrahydrofuran and their structures are studied by X-ray diffraction analysis. Complex I forms orthorhombic crystals with space group Pna21, a = 9.778(1) , b = 16.042(2) , c = 22.851(4) , Z = 4, R 1 = 0.0332; complex II crystallizes in monoclinic system: space group P21/c, a = 9.866(1) , b = 17.895(2) , c = 21.167(4) , = 100.75(2)°, Z = 4, R = 0.0422. The average Cr-(3-O) distances in compounds I and II are almost equal (1.943(3) and 1.927(3) ). An average length of the Cr-O bond in octahedral surrounding of metal atoms is different in complexes I and II (1.985(4) and 2.003(3) , respectively), which is specified by different oxidation states of the metal atom. The CrCr distances lie in an interval of 3.366(1)–3.337(1) .__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 4, 2005, pp. 266–272.Original Russian Text Copyright © 2005 by Glazunova, Boltalin, Troyanov.  相似文献   

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4.
The solubilities and nature of solid phases in the Co(NO3)2-(CH3)2SO-H2O system were studied at 25°C. A new congruently saturating compound was recovered: Co(NO3)2 · 4(CH3)2SO · 2H2O. The concentration boundaries of its crystallization in the system were determined. The compound was studied by the Schreinemakers wet residue method, X-ray powder diffraction, differential thermal analysis, crystal-optical analysis, and IR spectroscopy.  相似文献   

5.
尹汉东  王传华  邢秋菊 《中国化学》2005,23(12):1631-1636
Three bismuth(Ⅲ) complexes Bi(1,10-phen)[S2CN(CH3)2]2(NO3) (1), {Bi(S2COCH3)[S2CNC6Hs(CH3)]2}2 (2) and [Bi(S2CNBu2)2(CH3OH)(NO3)]∞ (3) were synthesized and characterized by elemental analysis and IR spectra. Their crystal structures were determined by X-ray single crystal diffraction analysis. Studies show that complex 1 has a monomeric structure with the central bismuth atom eight-coordinated in a capped distorted pentagonal bipyramidal geometry. The complex 2 takes centrosymmetric dimeric structure and the bismuth atoms are seven-coordinated in distorted pentagonal bipyramidal geometry.In complex 3, the bismuth atoms are seven-coordinated in distorted pentagonal bipyramidal geometry by bridging nitrate O atoms and the resulting structure is onedimensional infinite chain polymer.  相似文献   

6.
The cyclopentadienylchromium carbonyl thiocarbonyls Cp2Cr2(CS)2(CO)n (n = 4, 3, 2, 1) have been studied by density functional theory using the B3LYP and BP86 functionals. The lowest energy Cp2Cr2(CS)2(CO)4 structure can be derived from the experimentally characterized unbridged Cp2Cr2(CO)6 structure by replacing the two terminal carbonyl groups furthest from the Cr-Cr bond with two terminal CS groups. The two lowest energy Cp2Cr2(CS)2(CO)3 structures have a single four-electron donor η2-μ-CS group and a formal Cr-Cr single bond of length ∼3.1 Å. In contrast to the carbonyl analogue Cp2Cr2(CO)5 these Cp2Cr2(CS)2(CO)3 structures are viable with respect to disproportionation into Cp2Cr2(CS)2(CO)4 and Cp2Cr2(CS)2(CO)2 and thus are promising synthetic targets. The lowest energy Cp2Cr2(CS)2(CO)2 structures have all two-electron donor CO and CS groups and short CrCr distances around ∼2.3 Å suggesting the formal triple bonds required to give the chromium atoms the favored 18-electron configurations. These Cp2Cr2(CS)2(CO)2 structures are closely related to the known structure for Cp2Cr2(CO)4. In addition, several doubly bridged structures with four-electron donor η2-μ-CS bridges are found for Cp2Cr2(CS)2(CO)2 at higher energies. The global minimum Cp2Cr2(CS)2(CO) structure is a triply bridged triplet with a CrCr triple bond (2.299 Å by BP86). A higher energy singlet Cp2Cr2(CS)2(CO) structure has a shorter Cr-Cr distance of 2.197 Å (BP86) suggesting the formal quadruple bond required to give each chromium atom the favored 18-electron configuration.  相似文献   

7.
用量子化学密度泛函方法,在B3LYP/6-31G*水平下研究了叔丁基自由基(CH3)3C和NO2气体的反应机理.研究表明,该反应是在单、三态势能面上的多通道反应.不同反应通道的产物不同,单态下反应更容易发生.常温下对于一个敞开体系(例如在大气当中),(CH3)3C自由基和NO2作用主要生成比较稳定的化合物(CH3)3CONO和(CH3)3CNO2.这对于消除大气污染起到一定的作用.  相似文献   

8.
A new complex with mixed-quadriligand [Ce(CH2=C(CH3)-COO)2(NO3)(phen)]2 has been synthesized in aqueous solution of slight acidity and characterized by elementary analysis, IR and TGA. The crystal structure determination shows that the complex belongs to triclinic, space group P1, a=9.614?, b=10.047?, c=11.821?, Z=2, α=100.88(3)°, β=106.29(3)°, γ=97.93(2)°, V=1054(5)?3, Dc=1.741g·cm-3, F(000)=546.00, μ(MoKα)=22.06cm-1. And the crystal is consisted of a binuclear molecule. The coordina-tion of Ce3+ is nine.  相似文献   

9.
The structures of the crystals of Ba4[trans(N)-Co(Ida)2]3[cis-(N)-Co(Ida)2]2(ClO4)3 · 19.46H2O · 2CH3OH (I) and Ba[trans-(N)-Co(Ida)2]2 · 7H2O (II) (H2Ida is iminodiacetic acid) were determin by X-ray diffraction. The crystals of I containing two geometric isomers of the complex anions [Co(Ida)2] were obtained by a slow cooling of a hot solution, which contained initially only the cis-isomer. One Ba atom in I interacts with the trans-complex and with two cis-complexes to give a three-dimensional framework in crystal I. The positive charge of the last framework is compensated by one more trans-complex and by the perchlorate ions, one of which acts as a bidentate ligand with respect to the Ba atom. The crystals of II are built of the chains with the alternating Ba atoms and the trans-(N)-[Co(Ida)2] anions. The other anions of the same structure are each “suspended” to the Ba atoms of the chain. Original Russian Text ? M. Zabel, A.I. Poznyak, V.I. Pawlowskii, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 11, pp. 831–836.  相似文献   

10.
Preparation of the following new m-SF5CF2CF2C6H4X derivatives has been achieved: X=N3(2), Br(3), OC(O)CHCH2(4), CHCH2(5). The compounds were characterized by their respective IR, NMR, mass spectra (MS) and high resolution mass spectrometry (HRMS). An improved yield of SF5(CF2)2C6H5 (1) is also reported along with the synthesis of the polyacrylate (6) and polystyrene (7) from their respective monomers.  相似文献   

11.
The crystal structure of [(C5Me4Et)3Rh33-Se)2](PF6)2 and [(C5Me4Et)2Rh22-Cl)3]PF6, obtained in the reaction of [(C5Me4Et)Rh(C6H6)](PF6)2 with ZnSe in 4M HCl under hydrothermal conditions, is determined. In agreement with the 18VE rule, the triangular cluster contains single metal-metal bonds (Rh-Rh 2.864(1) ?), whereas they are absent in the binuclear complex (Rh ...Rh 3,216(1) ?). Original Russian Text Copyright ? 2009 by P. A. Abramov, M. N. Sokolov, A. V. Virovets, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 1, pp. 169–172, January–February, 2009.  相似文献   

12.
咸春颖  林苗 《无机化学学报》2003,19(9):1030-1032
The new complex [Ce(CH2=C(CH3)COO)2(NO3)(Phen)]2 was prepared in ethanol-aqueous solution with 8-hydroxyquinoline as the acidity regulator. Its crystal structure was determined by X-ray diffraction analysis. The title complex is triclinic, space group P1, a=1.00832(3)nm, b=1.02858(8)nm, c=1.12350(8)nm, α=113.9250(10)°, β=103.8210(10)°, γ=81.4650(10)°, V=1.03252(14)nm3, Z=1, Dc=1.700g·cm-3, F(000)=522. The coordination number of Ce3+ is nine. CCDC: 211278.  相似文献   

13.
Oxo/hydoxo zirconium(IV) complex of the general formula [Zr63-O)43-OH)4(OOCCH2tBu)92-OH)3]2 has been isolated, when Zr(OiPr)4 reacted with a 2-fold excess of 3,3-dimethylbutyric acid. Single crystal X-ray diffraction data, collected at 103 and 153 K, showed that the studied compound crystallizes in hexagonal system (P63/m (no. 176)). Structure consists of dimers composed of [Zr63-O)43-OH)4(OOCCH2tBu)9] sub-units, linked by six μ2-OH bridges. Infrared spectroscopic studies proved the presence of hydroxo groups in the structure of studied clusters and formation of different types of oxo/hydroxo bridges. The application of variable temperature infrared spectroscopy and differential scanning calorimetry revealed that the structure of this complex undergoes the phase transitions at 143–183 and 203–293 K. Comparison of spectral and crystallographic data suggests that these phase transitions might be related to changes in the strength of Zr–O bonds of μ2-OH bridges linking complex sub-units, and change in symmetry of the crystal lattice (from hexagonal to trigonal). Analysis of thermogravimetric data showed that decomposition of [Zr63-O)43-OH)4(OOCCH2tBu)92-OH)3]2 proceeds with complete conversion to ZrO2 (monoclinic form) between 603 and 803 K.  相似文献   

14.
15.
The fluorocarbon soluble, binuclear ruthenium(I) complexes [Ru(μ-O2CMe)(CO)2LF]2, where LF is the perfluoroalkyl substituted tertiary phosphine, P(C6H4-4-CH2CH2(CF2)7CF3)3, or P(CH2CH2(CF2)5CF3)3, were synthesized and partition coefficients for the complexes in fluorocarbon/hydrocarbon biphases were determined. Catalytic hydrogenation of acetophenone to 1-phenylethanol in benzotrifluoride at 105 °C occured in the presence of either [Ru(μ-O2CMe)(CO)2P(C6H4-4-CH2CH2(CF2)7CF3)3]2 (1) or [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 (2). The X-ray crystal structure of [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 was determined. The compound exhibited discrete regions of fluorous and non-fluorous packing.  相似文献   

16.
The reaction of with p-CH3C6H4S(O)2O(CH2)3C6H5 produces (η5-C5H5)(OC)3Mo(CH2)3C6H5. This is only the second structurally characterized organometallic species in which an aromatic moiety is separated by three or more methylene groups. The alkyl chain adopts a staggered conformation, the Mo-C(1)-C(2)-C(3)-C(4) unit is nearly coplanar, and the alkyl chain eclipses the trans-carbonyl group on Mo. NMR evidence indicates that this conformation is preserved in solution.  相似文献   

17.
运用量子化学密度泛函理论UB3LYP/6-311+G*和高级电子相关校正的偶合簇(CCSD(T)/6-311+G*)方法,对CH3CH2,CH3CHCl和CH3CCl2自由基与NO2反应的机理和动力学进行了理论研究,得到了体系的势能面信息和可能的反应机理.根据计算得到的各反应热力学参数及反应能垒,采用传统过渡态理论计算了各反应在温度T=298 K和T=700 K时的速率常数.研究结果表明,该类反应均通过1个中间体和1个过渡态生成产物,产物分别为CH3CHO+HNO,CH3CHO+ClNO和CH3CClO+ClNO.  相似文献   

18.
0 引言 稀土是一类具有特殊结构和性质的元素,稀土元素不仅大量用于工业,而且在农业和医学领域也有广泛应用 [1,2].其中,镧系离子以其独特的光、电、磁、催化和分析等性能而受到人们的广泛关注,并进行了大量的研究.镧系离子本身发光效率低,目前,设计并合成含有稀土离子La3+和Eu3+的超分子配合物,作为发光分子器件和荧光探针成为稀土配位化学,材料科学,超分子化学,分析化学和生物化学等研究领域的热点课题之一 [3~8].但对它们的热化学行为的研究鲜见文献报道.  相似文献   

19.
Quantitative IR investigation of solid-state [Co(NH3)5ONO]XY[Co(NH3)5NO2]XY (XY=Cl2, Br2, I2, (NO3)2 Cl; NO3) linkage isomerization in KBr pellets has shown the kinetics to depend upon the outer-sphere anion. The red shift of the 5(ONO) band during isomerization is a linear function of transformation degree.  相似文献   

20.
用X-射线衍射法测定了[C5H4C(CH3)(C3H7)CH2CH=CH2]NdMg2(μ3-OH)(μ3-Cl)(μ2-Cl)3(THF)4Cl的晶体结构。它属三斜晶系,空间群为<  相似文献   

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