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1.
Compounds [Cu2(CH2FCOO)4· 2CH3CN](CH3CN) (I) and Ag3(CF3COO)3(CH3CN)2(II) were synthesized and studied by X-ray structural analysis. Crystals Iare monoclinic, space group C2/c, a= 27.854(6), b= 8.286(2), c= 19.428(4) Å, = 106.82(3)°, V= 4292(2) Å3, Z= 8, R 1= 0.0426; crystals IIare triclinic, space group , a= 8.676(2), b= 9.819(2), c= 11.961(2) Å, = 95.27(3), = 109.59(3)°, = 104.60(3)°, V= 911.4(3) Å3, Z= 2, R 1= 0.0252. Structure Iis composed of the structural units (lanterns) typical of copper(II) carboxylates. The presence of an additional acetonitrile molecule noncoordinated by the copper atoms makes it possible to consider compound Ias a lattice clathrate. Structure IIhas no analogs among the silver carboxylates. It simultaneously contains silver atoms with coordination numbers varying from 2 to 4.  相似文献   

2.
《Solid State Sciences》2003,5(7):1041-1046
The salt para methyl phenyl dimethyl ammonium tetrachloroantimonate (III) crystallizes in the monoclinic system with space group Cc. The unit cell dimensions are: a=13.780(1) Å, b=14.943(2) Å, c=8.192(1) Å, β=113.39(1)°, with Z=4. The structure consists of ammonium cations and polynuclear anions in which distorted SbCl5 square pyramids sharing a common Cl atom are held together in infinite chains parallel to the c axis. These chains are themselves interconnected by means of the NH⋯Cl hydrogen bonds. Differential scanning calorimetry study was carried out. The Raman of polycrystalline samples have been recorded at different temperatures between 77 and 300 K. A low-temperature phase transition at 230 K of order-disorder type was found.  相似文献   

3.
[Ni(CH(3)COO)(2)·(NH(2)CH(2)Ph)(4)] complex was synthesized using benzylamine and nickel acetate. The molecular structure of this complex was obtained by single crystal X-ray diffraction and characterized by elemental analysis, IR spectrometry and thermal analysis. The complex crystallized in the monoclinic space group P2(1)/n with cell parameters a=11.234(4)?, b=6.459(2)?, c=22.647(8)?, α=90.00, β=91.149(4)°, γ=90.00, V=1642.8(10)?(3), Z=2. The structure has been solved by direct methods and refined to R(1)=0.0876 for 6377 observed reflections I>2σ(I). Magnetic studies for complex show the data over the whole temperature range 5-300 K are well fitted to the Curie-Weiss law with C=1.03 cm(3) K mol(-1) and θ=-1.38 K. This fitting indicates antiferromagnetic interaction between the Ni ions and the metal center exhibits distorted octahedral coordination geometries. The thermal analysis was carried out to understand the thermal stability of the title complex.  相似文献   

4.
A new cadmium coordination polymer based on imidazole-4,5-dicarboxylic acid (H3IDC) and 4,4′-bipyridine (Bipy), {[Cd9(IDC)2(HIDC)6(Bipy)4] · 2N(CH3)(CH2CH3)2 · 2DMF} n , has been synthesized under solvothermal conditions and characterized by energy dispersive X-ray spectroscopy, elemental analysis, FT-IR spectroscopy, thermal analysis, and single crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pnnm with a = 20.530(2) Å, b = 15.5957(14) Å, c = 16.3846(15) Å, α = β = γ = 90°, V = 5245.9(9) Å3, and Z = 2. The complex exhibits a 3-D structure with channels along the c-axis, in which the free N,N-dimethylformamide and methyl-diethyl-amine molecules are located. The thermal behavior and luminescence of this complex have also been studied in the solid state.  相似文献   

5.
T A dinuclear cadmium complex[Cd2(phen)2(C14H11O3)4(CH3CH2OH)]·(CH3OH)·(H2O)has been synthesized with benzilic acid and 1,10-phenanthroline by hydrothermal method.The crystal structure was determined bv X-ray diffraction with crystal parameters as follows:triclinic system with space group P-1,α=1.21298(10),b=1.32586(1 1),c=2.4815(2)nm,α=76.2630(10),β=81.4500(10),γ=69.1700(10)°V=3.6143(5)nm3,Dc=1.438g/cm3,Z=1,F(000)=1600,the final GOOF=0.937,R=0.0521 and wR=0.1328.In the title complex,the dinuclear structure is defined by carboxyl oxygen atoms adopting a monodentate bridged coordination mode.The coordination environment of Cd(Ⅱ)ion is CdO4N2,giving a distorted octahedral coordination geometry.TG analysis shows that the title complex is stable under 140℃.  相似文献   

6.
7.
Using ESR and IR spectroscopy, the structures of >Si(O–C·=O)(CH2–CH3) (1) and >Si(CH2–CH·–CH3)(CH2–CH3) (2) radicals were deciphered. The directions and kinetic parameters of reactions of intramolecular rearrangements in these radicals were determined. The reactions of hydrogen atom abstraction in radical (1) from the CH2 and CH3 groups were studied. It was found that the endothermic reaction of hydrogen atom abstraction from the methyl group occurs at a higher rate than the exothermic reaction with the methylene group. The differences are determined by changes in the size of a cyclic transition state. Based on the experimental data, the strengths of separate C–H bonds in surface fragments are compared. The rearrangement >Si(CH2–CH·–CH3)(CH2–CH3) >Si(C·(CH3)2)(CH2–CH3) was discovered and its mechanism was determined. One of its steps is the skeletal isomerization Si- (2)- . (1)Si- (1)- . (2). Experimental data are analyzed using the results of quantum-chemical calculations of model systems.  相似文献   

8.
林进  张萍  王昭煜  王宏根 《结构化学》1999,18(3):188-191
用X-射线晶体结构衍射法测定了[C5H4C(CH3)2CH2CH=CH2]Sm(OH)Cl·2MgCl2·4THF的晶体结构。它属三斜晶系,空间群为P^-1,a=10.773(2),b=12.836(3),c=15.478(3)A,a=111.46(3),β=107.71(3),γ=92.54(3)°,V=1868(1)A^3,Mr=827.91,Dx=1.472g/cm^3,μ=2.0006mm  相似文献   

9.
The reaction of 1-phenacylimidazole with W(CO)6 in a 1:1 molar ratio under irra- diation with a high-pressure Hg lamp mainly yielded the title compound (C29H26N4O7W, Mr = 726.39), which is of orthorhombic, space group Pbca with a = 27.665(4), b = 7.7807(12), c = 27.803(4) (A), V = 5984.8(16) (A)3, Z = 8, Dc = 1.612 g/cm3, λ(MoKα) = 0.71073 (A), μ = .3.911 mm-1, F(000) = 2864, R = 0.0583 and wR = 0.1502 for 3356 observed reflections (I > 2σ(I)). The crystal structural analysis indicates that in the coordination geometry of tungsten, 1-phenacylimidazole acts as a monodentate ligand and two imidazole ligands locate in a cis-position.  相似文献   

10.
11.
We report a high-quality, ab initio, full-dimensional global potential energy surface (PES) for the Cl((2)P, (2)P(3/2)) + CH(4) reaction, which describes both the abstraction (HCl + CH(3)) and substitution (H + CH(3)Cl) channels. The analytical PES is a least-squares fit, using a basis of permutationally invariant polynomials, to roughly 16,000 ab initio energy points, obtained by an efficient composite method, including counterpoise and spin-orbit corrections for the entrance channel. This composite method is shown to provide accuracy almost equal to all-electron CCSD(T)/aug-cc-pCVQZ results, but at much lower computational cost. Details of the PES, as well as additional high-level benchmark characterization of structures and energetics are reported. The PES has classical barrier heights of 2650 and 15,060 cm(-1) (relative to Cl((2)P(3/2)) + CH(4)(eq)), respectively, for the abstraction and substitution reactions, in good agreement with the corresponding new computed benchmark values, 2670 and 14,720 cm(-1). The PES also accurately describes the potential wells in the entrance and exit channels for the abstraction reaction. Quasiclassical trajectory calculations using the PES show that (a) the inclusion of the spin-orbit corrections in the PES decreases the cross sections by a factor of 1.5-2.5 at low collision energies (E(coll)); (b) at E(coll) ≈ 13,000 cm(-1) the substitution channel opens and the H/HCl ratio increases rapidly with E(coll); (c) the maximum impact parameter (b(max)) for the abstraction reaction is ~6 bohr; whereas b(max) is only ~2 bohr for the substitution; (d) the HCl and CH(3) products are mainly in the vibrational ground state even at very high E(coll); and (e) the HCl rotational distributions are cold, in excellent agreement with experiment at E(coll) = 1280 cm(-1).  相似文献   

12.
The title compound has been synthesized by the reaction of HgI2 and [(CH3)3- NCH2CH2N(CH3)3]I2 with pH = 7.5 at room temperature, and its crystal structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group P21/c with a = 8.3075(8), b =15.8084(19), c =15.390(2)(°A), β = 95.192(4)o, V = 2012.9(4)(°A)3, Z = 2, Dc = 2.824 g/cm3, F(000) = 1502, C14H39N4O2Hg2I8, Mr = 1711.87, μ(MoKα) = 13.768 mm-1, the final R = 0.0465 and wR = 0.1293 for 3046 observed reflections with I > 2(I). The title compound consists of cations ([C8H22N2]2+) and anion (HgI42-), which are combined by static attracting forces to form the so-called organic-inorganic hybrid material.  相似文献   

13.
A cation–anion metal string complex with neutral axial ligands, [Ni3(dpa)4(CH3CN)2] · (ClO4)2 · (CH3CN) · H2O (1) where dpa? is 2,2′-dipyridylamine anion, was synthesized and characterized by elemental analysis, IR, fluorescence, UV, and CV spectroscopic methods, and single crystal X-ray analysis. The Ni–Ni distances in 1 are longer than those in [Ni3(dpa)4(CH3CN)2] · (PF6)2 · 3.14CH3CN (2) and [Ni3(dpa)4F2] · [Ni3(dpa)4(H2O)2] · (BF4)2 · 2CH3OH, indicating that the counter anions affect the Ni–Ni distances of trinickel string complexes. Compared with Ni3(dpa)4Cl2 and Ni3(dpa)4(ClO4)2, 1 also has different fluorescence, UV, and CV properties. Therefore, this study clearly indicates that ligands and counter anions largely influence the structures and properties of trinickel string complexes.  相似文献   

14.
The reaction of bis(dibromophenylstannyl)methane with 1, 3-bis(3, 5-dimethyl- pyrazol-1-yl)propane in a 1:1 or 1:2 ratio yields only 1:1 adduct which partly hydrolyzes to the title complex (C26H38Br6N4O2Sn2, Mr = 1155.42) during crystal growing. The title complex is of triclinic, space group P ī with a = 10.886(1), b = 12.508(1), c = 13.879(1) ?, α = 85.762(2), β = 85.159(2), γ = 84.020(2)°, V = 1868.8(4) ?3, Z = 2, Dc = 2.046 g/cm3, λ(MoKα) = 0.71073 ?, μ = 7.778 mm-1, F(000) = 1088, R = 0.0488 and wR = 0.1157 for 7560 observed reflections with I ≥ 2σ(I). The crystal structure analysis indicates that there is no direct interaction between the ligand and bis(dibromophenylstannyl)methane, and two tin atoms are bridged by two bromide atoms from the partial hydrolysis of this adduct.  相似文献   

15.
《Solid State Sciences》2004,6(2):229-233
Two new organically templated zinc selenites MIL-86 or [H2N(CH2)2NH2]2·Zn4(SeO3)4 and MIL-87 or [H3N(CH2)3NH3]4·Zn4(SeO3)8 have been prepared by the reaction of ZnO with SeO2 under hydrothermal conditions in the presence of organic amines. Crystal data: MIL-86, monoclinic, space group P21/n, a=6.7712(4) Å, b=9.4520(5) Å, c=8.0295(4) Å, β=113.601(1)°, V=470.91(4) Å3; MIL-87, orthorhombic, space group Pbcm, a=8.8311(3) Å, b=7.8391(2) Å, c=16.2992(4) Å, V=1128.36(6) Å3. MIL-86 combines the structural features of templated networks and coordination polymers. Its structure is built up from ZnO3N tetrahedra and SeO3 pseudo-pyramids as the polyhedral building units. The ZnN bond corresponds to a direct link between zinc and the ethylenediamine template. In the other hand, MIL-87 is built up from chains of vertex-linked ZnO4 and SeO3 building units crosslinked by 1,3-diammonium propane cations. These structures are understood by comparison with the already known organically templated zinc phosphites.  相似文献   

16.
Tetraalkylammonium chlorides peroxosolvates (CH3)4NCl·H2O2 and (C2H5)4NCl·H2O2 were synthesized. The composition of the solvates was proved by chemical analysis; their X-ray patterns, IR spectra, and thermograms were obtained. The solubility of the solvates in water and their stability in aqueous solutions were investigated.  相似文献   

17.
标题配合物是由三齿配体Ⅳ,Ⅳ-二(2-苯并咪唑甲基)亚胺(IDB)与NiSO4·6H2O在甲醇-乙醇溶液中反应得到的紫色 晶体.X射线衍射测定了其单晶结构.结构分析表明,镍(Ⅱ)分别与两个IDB配体中的苯并咪唑的四个氮和胺基的两个 氮配位形成畸变的八面体构型.研究了纳米金和小牛胸腺DNA对配合物荧光的影响,探讨了配合物的荧光猝灭与恢复 的可能机理.  相似文献   

18.
无机-有机杂化钒氧酸盐由于其结构的多样性以及在催化、医药、光、电、磁等材料领域中的应用前景而受到人们的广泛关注。近年来这一研究领域的重大进步是将有机氮配体或者过渡金属配合物直接连接到矾氧骨架上以获得各种新奇结构。合成出许多属于L/V/O、MXLY/V/O、L/P/V/O和MXLY  相似文献   

19.
Single crystals of (NH4)2[(UO2)2C2O4(CH3COO)4] · 2H2O have been synthesized and studied. The compound crystallizes in the orthorhombic system with the unit cell parameters a = 6.9225(14) Å, b = 12.327(3) Å, c = 14.619(3) Å, space group Immm, Z = 2, and V = 1247.6(5) Å3. The main structural units of the crystals are the isle binuclear groups [(UO2)2C2O4(CH3COO)4]2? belonging to the crystal-chemical group A2K02B 4 01 (A = UO 2 2+ , K02 = C2O 4 2? , B01 = CH3COO?) of the uranyl complexes. The uranium-containing groups are linked into a three-dimensional framework due to electrostatic interaction with the ammonium cations and through a system of hydrogen bonds involving atoms of the water molecules, oxalate and acetate ions, and ammonium and uranyl cations.  相似文献   

20.
Metastable ion decompositions, collision-activated dissociation (CAD), and neutralization-reionization mass spectrometry are utilized to study the unimolecular chemistry of distonic ion ·CH2CH2CH?OH (2) and its enol-keto tautomers CH3CH=CHOH (1 ) and CH3CH2CH=O (3). The major fragmentation of metastable 1–3 is H· loss to yield the propanoyl cation, CH3CH2C≡O+. This reaction remains dominant upon collisional activation, although now some isomeric CH2=CH-CH+ OH is coproduced from all three precursors. The CAD and neutralization-reionization (+NR+) spectra of keto ion 3 are substantially different from those of tautomers 2 and 1. Hence, 3 without sufficient energy for decomposition (i. e. , “stable” 3) does not isomerize to the ther-modynamically more stable ions 2 or 1, and the 1,4-H rearrangement H-CH2CH2CH=O(3 ) → CH2CH2CH+ O-H (2 ) must require an appreciable critical energy. Although the fragment ion abundances in the + NR + (and CAD) spectra of 1 and 2 are similar, the relative and absolute intensities of the survivor ions (recovered C3H6O ions in the +NR+ spectra) are markedly distinct and independent of the internal energy of 1 and 2 . Furthermore, 1 and 2 show different MI spectra. Based on these data, distonic ion 2 does not spontaneously rearrange to enol ion 1 (which is the most stable C3H6O of CCCO connectivity) and, therefore, is separated from it by an appreciable barrier. In contrast, the molecular ions of cyclopropanol (4 ) and allyl alcohol (5 ) isomerize readily to 2 , via ring opening and 1,2-H? shift, respectively. The sample found to generate the purest 2 is α-hydroxy-γ-butyrolactone. Several other precursors that would yield 2 by a least-motion reaction cogenerate detectable quantities of enol ion 1 , or the enol ion of acetone (CH2=C(CH3)OH, 6 ), or methyl vinyl ether ion (CH3OCH=CH 2 , 7 ). Ion 6 is coproduced from samples that contain the —CH2—CH(OH)—CH2— substructure, whereas 7 is coproduced from compounds with methoxy substituents. Compared to CAD, metastable ion characteristics combined with neutralization-reionization allow for a superior differentiation of the ions studied.  相似文献   

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