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1.
通过三核铁盐[Fe3O(O2CCH3)6(H2O)3]C1在吡啶溶液中水解聚合得到铁氧簇合物[Fe11O6(OH)6(O2CCH3)15](C5H5N)6。晶体结构表明11个铁离子(Ⅲ)中6个位于扭曲的三棱柱的顶点上,其余5个分别位于三棱柱的每个面之外。铁离子(Ⅲ)之间以氧桥或者羟基氧桥相连。变温磁化率证实铁离子(Ⅲ)之间是反铁磁耦合的。  相似文献   

2.
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   

3.
The electrical conductive molecular crystals (Me3NEt)[Pd(dmit) 2]2 and (NEt4)[Pd (dmit) 2]2 (dmit = 4,5-dimercapto-1,3-dithiole-2-thione) have been prepared, and their crystal structures and conductivity-temperature curves have been determined. The fact that the conductivity at room temperature of (Me3NEt)[Pd(dmit) 2]2 (σ = 58 Ω-1 cm-1) is much higher than that of (Net4)-[Pd(dmit)2]2 (σ = 2.2 Ω-1.cm-1) has been rationally explained by the results of energy band calculations. (MeNEt3)[Pd(dmit)2]2 belongs to monoclinic system, P21/m space group and (Net4)[Pd (dmit)2]2 belongs to triclinic system, space group. The structural conducting component of the crystals is the planar coordinative anion [Pd(dmit)2]0.5- which forms the face-to-face dimmer. [Pd(dmit)2]- 2These dimers have been further constructed to be a kind of two-dimensional (2-D) conductive molecular sheet by means of S_S intermolecular interactions. The tiny difference of the above 2-D molecular sheets of the two title crystals has resulted in one order of magnitude difference of conductivities.  相似文献   

4.
配合物Fe(pda)2(H2O)4和[FeCo(pda)4(H2O)4]n的合成与晶体结构   总被引:1,自引:0,他引:1  
采用水热法合成了2个3-(3-吡啶基)丙烯酸的配合物:Fe(pda)2(H2O)4(1)和[FeCo(pda)4(H2O)4]n(2)(pda=3-(3-吡啶基)丙烯酸),用红外光谱、元素分析、热重-差热以及X-射线衍射单晶结构分析进行了表征.2个配合物都属于单斜晶系,配合物1的空间群为P21/n,配合物2的为P21/c.配合物1是一个pda配体中仅吡啶基氮原子参与配位、而羧基上的氧原子未参与配位的单核结构,通过大量的氢键作用形成三维超分子体系.2是pda配体桥联Fe和Co的异核二维层状配位聚合物;配体吡啶基上的氮原子和羧基上的氧原子都参与了配位,其中羧基采用单齿配位模式.  相似文献   

5.
The magnetoresistance study on TPP[M(Pc)(CN)2]2 (M=Fe, Co, Fe0.30Co0.70) salts is reported. These three salts have similar columnar structures, nevertheless exhibit different electrical behaviors. TPP[Fe(Pc)(CN)2]2 exhibits anisotropic giant negative magnetoresistance, while TPP[Co(Pc)(CN)2] exhibits large positive magnetoresistance. The alloyed compound, TPP[Fe0.30Co0.70 (Pc)(CN)2]2, also exhibits anisotropic negative magnetoresistance, although the decrease in the resistivity under the magnetic field is less than that of TPP[Fe(Pc)(CN)2]2. The g-tensor anisotropy in the [Fe(Pc)(CN)2] unit qualitatively explains the field-orientation dependence of the negative magnetoresistance. Magnetic fluctuation associated with a weak-ferromagnetic transition is suggested as a possible origin of the giant negative magnetoresistance.  相似文献   

6.
利用四氟苯甲酸(H2tfbdc),1,10-邻菲咯啉与四水醋酸钴在甲醇和水混合溶剂中的反应,得到了标题配合物[Co(O2CC6HF4)2(Phen)2]。用元素分析、红外光谱、热重分析、循环伏安、X-衍射单晶结构分析等对其进行了表征。晶体结构表明,标题配合物的晶体属单斜晶系,空间群为P21/c,晶胞参数:a=1.3719(8)nm,b=1.5956(10)nm,c=1.5849(10)nm,β=106.327(10)°;每个钴离子与来自2个2,3,5,6-四氟苯甲酸分子的2个氧原子和2个1,10-邻菲咯啉分子的4个氮原子配位,形成变形的八面体配位构型。[Co(O2CC6HF4)2(Phen)2]独立结构单元通过两种氢键(C-H…F和C-H…O)形成三维的超分子网络结构。  相似文献   

7.
The Mn7(HOXO3)4(XO4)2 (X=As, P) compounds have been synthesized by using hydrothermal conditions. The arsenate phase was obtained under autogeneous pressure at 170°C. However, more drastic conditions at both pressure and temperature were necessary in the attainment of the phosphate compound. The crystal structure of Mn7(HOAsO3)4(AsO4)2 was solved using single-crystal data. The unit-cell parameters are a=6.810(3) Å, b=8.239(2) Å, c=10.011(4) Å, α=104.31(2)°, β=108.94(3)°, γ=101.25(2)°. Triclinic, P-1 with Z=1. The isostructural Mn7(HOPO3)4(PO4)2 phase was characterized from X-ray powder diffraction techniques. The crystal structure of both compounds consists of zig-zag chains constructed by dimeric edge-sharing Mn2O10 octahedra linked through the MnO5 trigonal bipyramids. The three-dimensional framework is completed by the connection between isolated MnO6 entities to the dimers octahedra and trigonal bipyramids. The existence of hydrogenarsenate and hydrogenphosphate anions has been confirmed by IR and Raman spectroscopies. Magnetic measurements indicate the existence of antiferromagnetic interactions in both compounds, which are slightly stronger in the arsenate phase.  相似文献   

8.
Crystal structures of two new misfit compounds, [SrGd0.5S1.5]1.16NbS2 and [Sr(Fe,Nb)0.5S1.5]1.13NbS2, were determined through the composite approach, i.e., by refining each subpart (Q, H-parts, and the common part) of these composite materials, separately. The Q-part is a three-atom-thick layer, with the NaCl-type structure, where external SrS planes enclose the inner GdS or (Fe,Nb)S plane; the structural difference between these two compounds lies in the central layer within the Q-part: Gd and S atoms are in special positions (octahedral coordination), while Fe and S atoms are statistically distributed on split (×4) positions (tetrahedral coordination) around a central unique site (=special position occupied by Nb). The H-part is a sandwich of sulfur planes enclosing the inner Nb plane as observed for the structure of the binary compound NbS2 itself. The Sr-Gd derivative shows a paramagnetic behavior in the whole studied temperature range (2-300 K). On the other hand, antiferromagnetic interactions occur in the Sr-Fe derivative; the complex magnetic behavior of this compound is related to the statistical distribution of Fe atoms which leads to frustration of the magnetic interactions. At room temperature, experimental values obtained from Mössbauer spectrum correspond to Fe3+ in tetrahedral sulfur environment: isomer shift δ=0.32 mm s−1, and quadrupole splitting ΔE=0.48 mm s−1.  相似文献   

9.
稀土配合物[Nd(o-NO2-C6H4COO)3(DMF)2]2的合成及其晶体结构   总被引:2,自引:0,他引:2  
赵丽芳  陈亚芍 《化学学报》2007,65(8):667-672
合成了一种新的双核倒反中心的稀土钕配合物[Nd(o-NO2-C6H4COO)3(DMF)2]2. 通过元素分析, 核磁共振谱和红外光谱对配合物的组成和结构进行了表征, 用热重分析研究了该配合物的热稳定性, 用X射线单晶衍射法测定了其晶体的结构. 钕配合物[Nd(o- NO2-C6H4COO)3(DMF)2]2晶体属三斜晶系, 空间群P-1, 晶胞参数a=1.18652(12) nm, b=1.24784(13) nm, c=1.29958(13) nm, α=64.220 (1)°, β=66.306 (1)°, γ=71.825 (1)°, V=1.5645 (3) nm3, Dc=2.167 mg/m3, Z=2, μ=3.415 mm-1, F(000)=986. 配合物中每个Nd(Ш)被4个邻硝基苯甲酸根桥联, Nd(Ш)的配位数为8, 配位原子分别来自于5个邻硝基苯甲酸羧酸根的6个氧原子和2个DMF的羰基氧原子. 配合物中的氢键和ππ 堆积作用使其成为三维立体结构. 同时发现了标题配合物固体具有光致发光现象, 发光性能测试表明该配合物具有很好的荧光性质.  相似文献   

10.
The title compound {[(p-MeC6H4CH2)2Sn]2(O)(Cl)OC2H5}2 was synthesized by the reaction of bis(p-met-hylbenzyl)tin dichloride with KOH in ethanol. The crystal structure of the complex has been determined by X- ray diffraction. The crystal belongs to monoclinic, space group P21/c with a=1.114 0(19) nm, b=2.423 1(3) nm, c=2.521 1(3) nm, β=99.398(3)°, V=6.714(16) nm3, Z=4, Dc=1.493 g·cm-3, μ(Mo Kα)=15.94 cm-1, F(000)=3 024, R1=0.049 9, wR=0.101 7. The crystal structure shows that the coordination geometry of tin is a distorted trigonal bipyramid, and the ladder-like structure is shaped by three Sn2O2 planar four-membered rings. CCDC: 639682.  相似文献   

11.
By the reaction of a new donor molecule, ethylenedithiotetrathiafulvalenoquinone-1,3-dithiolemethide (1) with FeBr3, GaBr3 or FeCl3 in CH3CN/CS2 charge transfer (CT) salts of 1 with counteranions of FeBr4, GaBr4 or FeCl4 (12·FeBr4, 12·GaBr4 and 12·FeCl4) as plate crystals were obtained. Their crystal structures are apparently similar to each other, in which 1 molecules are dimerized in the parallel direction of their molecular long axes, and the dimers are stacked with changing the direction of the molecular long axes alternately to form a one- dimensional column. The counteranions intervene between the 1-stacked columns and are aligned in a zigzag manner. The room-temperature electrical conductivities of 12·FeBr4 and 12·GaBr4 are fairly high (10-15 S cm−1), but a small value (0.8 S cm−1) is obtained for 12·FeCl4. For all CT salts, temperature dependences of electrical conductivity are semiconducting in spite of very small activation energies (30-90 meV). Based on the comparison between their electrical conducting and magnetic properties, it is suggested that the d spins of FeBr4 or FeCl4 ions exert almost no influence on the π conducting electrons in the 1-stacked column.  相似文献   

12.
The reaction of Al, Ga, or In metals and H5IO6 in aqueous media at 180 °C leads to the formation of Al(IO3)3, Ga(IO3)3, or In(IO3)3, respectively. Single-crystal X-ray diffraction experiments have shown In(IO3)3 contains the Te4O9-type structure, while both Al(IO3)3 and Ga(IO3)3 are known to exhibit the polar Fe(IO3)3-type structure. Crystallographic data for In(IO3)3, trigonal, space group , a=9.7482(4) Å, c=14.1374(6) Å, V=1163.45(8) Z=6, R(F)=1.38% for 41 parameters with 644 reflections with I>2σ(I). All three iodate structures contain group 13 metal cations in a distorted octahedral coordination environment. M(IO3)3 (M=Al, Ga) contain a three-dimensional network formed by the bridging of Al3+ or Ga3+ cations by iodate anions. With In(IO3)3, iodate anions bridge In3+ cations in two-dimensional layers. Both materials contain distorted octahedral holes in their structures formed by terminal oxygen atoms from the iodate anions. The Raman spectra have been collected for these metal iodates; In(IO3)3 was found to display a distinctively different vibrational profile than Al(IO3)3 or Ga(IO3)3. Hence, the Raman profile can be used as a rapid diagnostic tool to discern between the different structural motifs.  相似文献   

13.
The phases Bi14MO24 (M=Cr, Mo, W) have been studied using differential scanning calorimetry, variable temperature X-ray powder diffraction and neutron powder diffraction. All three compounds were found to undergo a phase change, on cooling, from the previously reported tetragonal symmetry (I4/m) to monoclinic symmetry (C2/m). Transition temperatures were determined to be ∼306 K (M=W) and ∼295 K (M=Mo), whereas a gradual transition between 275 and 200 K was observed for M=Cr. The high and low temperature structures are very similar, as indicated by the relationship between the monoclinic and tetragonal unit cell parameters: am=√2at, bm=ct, cm=at, β∼135°. High-resolution neutron powder diffraction data, collected at 400 and 4 K, were used to establish the nature of the transition, which was found to involve a reduction in the statistical possibilities for orientation of the MO4 tetrahedra. However, in both tetragonal and monoclinic variants, a degree of orientational disorder of the tetrahedra occurs to give partially occupied sites in the average unit cell.  相似文献   

14.
本文研究了羰基钼(钨)与双(1-甲基咪唑-2-基)甲酮和双(1-甲基咪唑-2-基)甲烷以及双(1-甲基咪唑-2-基)乙烯的反应,获得了6个双齿螯合的双(1-甲基咪唑-2-基)甲酮,双(1-甲基咪唑-2-基)甲烷和双(1-甲基咪唑-2-基)乙烯四羰基金属衍生物,以及1个单齿配位的双(1-甲基咪唑-2-基)乙烯五羰基钨化合物。它们的结构通过红外,核磁以及X-射线单晶衍射分析得到确证。所有这些新化合物的电化学测试表明,它们只存在一个不可逆的氧化过程。  相似文献   

15.
Reaction between Os(CO)2(PPh3)3 and Me3SnH produces Os(SnMe3)H(CO)2(PPh3)2 (1). Multinuclear NMR studies of solutions of 1 reveal the presence of four geometrical isomers, the major one being that with mutually cis triphenylphosphine ligands and mutually trans CO ligands. Os(SnMe3)H(CO)2(PPh3)2 undergoes a redistribution reaction, at the trimethylstannyl ligand, when treated with Me2SnCl2 giving Os(SnMe2Cl)H(CO)2(PPh3)2 (2). Solutions of 2 again show the presence of four isomers but now the major isomer is that with mutually trans triphenylphosphine ligands and mutually cis CO ligands. The redistribution reaction of 1 with SnI4 produces Os(SnMeI2)H(CO)2(PPh3)2 (3) which exists in solution as only one isomer, that with mutually trans triphenylphosphine ligands and mutually trans CO ligands. Treatment of 3 with I2 cleaves the Os-H bond with retention of geometry giving Os(SnMeI2)I(CO)2(PPh3)2 (4). The crystal structure of 4 has been determined. No isomerization of the trans dicarbonyl complex 4 occurs when 4 is heated, instead there is a formal loss of “MeSnI” and formation of OsI2(CO)2(PPh3)2 (5).  相似文献   

16.
The compound EuAlF5, as well as the solid solutions Ca0.19(1)Eu0.81(1)AlF5, Sr0.15(1)Eu0.85(1)AlF5, Sr0.55(1)Eu0.45(1)AlF5, Sr0.77(1)Eu0.23(1)AlF5, and Ba0.62(1)Eu0.38(1)AlF5, crystallize in colorless tetragonal columns. These have been prepared by solid state reactions at 900°C, starting from mixtures of the binary fluorides. According to Vegard's rule the solid solution Sr1−xEuxAlF5 shows a linear dependence of the crystal volume on the molar ratio Eu/Sr. All crystal structures have been refined from single-crystal diffractometer data. EuAlF5 and the M1−xEuxAlF5 (M=Ca, Sr) compounds obtained are isotypic with β-SrAlF5. They crystallize in a superstructure in space group I41/a (no. 88) with 64 formula units and lattice parameters a≈19.9 Å, c≈14.3 Å. The structure is characterized by chains of trans-corner-sharing [AlF4/2F2/1] and branched [AlF5/1F1/2] octahedra forming a channel structure. Inside the channels isolated ordered dimeric units [AlF4/1F2/2]2 are located. The divalent metal atoms show coordination numbers 8 and 9; they connect the [AlF6] octahedra into a three-dimensional structure. Ba0.62(1)Eu0.38(1)AlF5 is isotypic with the corresponding Sr compound Ba0.43(1)Sr0.57(1)AlF5, and it crystallizes with 16 formula units and lattice parameters a=14.3860(7) Å, c=7.2778(3) Å in space group I4/m (no. 87). The network structure is identical with that of EuAlF5. Instead of the dimeric units, infinite chains [AlF4/1F2/2] of trans-corner-sharing [AlF6] octahedra extending along the c- axis are located inside the channels. The bridging fluorine atoms of this chain show large anisotropic displacement parameters, but no superstructure reflections have been observed for this compound.  相似文献   

17.
Treatment of a tetrahydrofuran solution of CrCl2(thf) with Na(hfac), hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate, followed by crystallization from diethyl ether, affords the six-coordinate chromium(II) complex Cr(hfac)2(thf)2. The crystal structures of Cr(hfac)2(thf)2 and the chromium(III) complex Cr(hfac)3 have been determined by single-crystal X-ray diffraction. Cr(hfac)2(thf)2 adopts a trans octahedral geometry, in which the Cr–O(hfac) and Cr–O(thf) distances are 1.936(3) and 2.019(6) Å, respectively. Cr(hfac)3 is an octahedral compound with a Cr–O distance of 1.943(5) Å. Structural comparisons with related molecules are given.  相似文献   

18.
本文合成了一个新的含有4-对甲基苯基-3,5-二(2-吡啶基)-1,2,4-三氮唑配体(L)的锰(Ⅱ)配合物,[MnL2(NCS)2]。其结构由X射线晶体学,红外和电喷雾离子质谱表征。在晶体结构中, 锰原子有一反演中心并由2个三芳基三氮唑配体的4个氮原子和2个反式硫氰根的2个氮原子八面体配位。磁性测定表明在75~300 K的温度范围内该配合物是顺磁性的。  相似文献   

19.
Combination of the [Ni(bpy)3]2+ cation complex and the [Pd(dmit)2] anion (dmit=C3S52−=1,3-dithiole-2thione-4,5-dithiolate) has resulted in the paramagnetic [Ni(bpy)3][Pd(dmit)2]·CH3CN compound, a suitable precursor for a molecular magnetic conductor. Its crystal structure consists of a Pd(dmit)2 anion arrangement that is quite different from segregated stack layers often found for M(dmit)2−based compounds. The reduction of the [Pd(dmit)2]- to the 2− charged anion in the title compound most probably is the result of a charge disproportionation between Pd(dmit)2 anions.  相似文献   

20.
Here we report the synthesis and characterization by X-ray diffraction, FTIR, UV-Vis and EPR spectroscopies, and the magnetic measurements of two new compounds: [Mn(NCS)2(bpe)2(H2O)2] (1) and [Fe(NCS)2(bpe)2(H2O)2] (2) (bpe = 1,2-bis(4-pyridyl)ethylene). Single-crystal structure analyses reveals discrete octahedral metal units that are assembled into 2D sheets through O-Hw?N(bpe) and O-Hw?S(thiocyanate) hydrogen bonds. The intermetallic M?M distances are 6.90 and 6.87 Å for 1 and 2, respectively. Supramolecular architectures are obtained by connections through H-bonds. Slight interactions are observed for compound 2.  相似文献   

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