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1.
The title compound was synthesized by reaction of Cu(ClO4)2, picolinic acid and carbamide in C2H5OH/CH3CN solution, and characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=14.0481(8), b=9.0130(5), c=18.626(1)?, V=2358.3(2)?3Z=4, Dx=1.771g·cm-3, μ=1.235mm-1 and F(000)=1276. The final R factor is 0.0440 for 1434 observed reflections. The X-ray analysis revealed that the copper(Ⅱ) atom is coordinated by two picolinic ligands in the equatorial plane, while the two oxygen atoms of perchlorate occupy the axial positions of octahedron with lengthened Cu-O distances, resulting in a 4+2 elongated octahedral environment. In the compound, there also exist two protonated carbamide cations for charge balance. CCDC: 195354.  相似文献   

2.
Single crystals of Cs4[(UO2)2(C2O4)(SO4)2(NCS)2] · 4H2O (I) and (NH4)4[(UO2)2(C2O4)(SO4)2(NCS)2] · 6H2O (II) have been synthesized and studied by X-ray diffraction. The crystals of both compounds are orthorhombic with the space group Pbam, Z = 2, and unit cell parameters a = 12.0177(3) ?, b = 18.6182(5) ?, c = 6.7573(10) ?, R = 0.0376 (I); a = 11.6539(9) ?, b = 18.3791(13) ?, c = 6.7216(5) ?, R = 0.0179 (II). The main structural units of crystals I and II are [(UO2)2(C2O4)(SO4)2(NCS)2]4− chains belonging to the crystal-chemical group A2K02B22M21 (A = UO22+, K02 = C2O42−, B2 = SO42−, M1 = NCS) of the uranyl complexes. The uranium-containing chains are joined into a three-dimensional framework due to a system of electrostatic interactions with the cesium or ammonium ions in the structure of I. In the structure of II, this framework is additionally stabilized by hydrogen bonds involving the outer-sphere water molecules and ammonium ions. Original Russian Text ? I.V. Medrish, A.V. Virovets, E.V. Peresypkina, L.B. Serezhkina, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 7, pp. 1115–1120.  相似文献   

3.
A single crystal of [Pd(NH3)4]3[Ir(NO2)6]2·H2O double complex salt is studied by X-ray diffraction. Crystallographic characteristics are as follows: a = 21.0335(5) ?, b = 8.0592(2) ?, c = 21.3452(5) ?, β = 91.254(1)°, V = 3617.43(15) ?3, P21/c space group, Z = 4, d x = 2.714 g/cm3. Single-layer pseudohexagonal packing of complex anions is determined along the [−1 0 1] direction in the structure. Complex cations and crystallization water molecules are located between the mentioned layers.  相似文献   

4.
Two new double complex salts [Pd(NH3)4]3[Rh(NO2)6]2 (I) and [Pd(NH3)4]3[Rh(NO2)6]2·H2O (II) are synthesized and characterized. The techniques to produce one-phase residues of the salts are developed. The crystallographic data for I: a = 18.915(2) ?, V = 6767.4 ?3, F-43c space group, Z = 8, d x = 2.548 g/cm3; II: a = 21.160(6) ?, b = 8.085(7) ?, c = 21.363(4) ?, β = 91.71(4)°, V = 3661.1(6) ?3, P21/c space group, d x = 2.357 g/cm3. Thermal properties of the obtained compounds in the hydrogen and helium atmosphere are studied. It is shown that the final product of their decomposition both in the inert and reducing atmosphere is a powder consisting of bimetallic nanosized particles (nanoalloy) of Pd0.59Rh0.41 (Fm-3m space group, a = 3.856(2) ?, crystallite size of 8–11 nm).  相似文献   

5.
Zr5Ir2In4 was synthesized by reaction of the elements in a glassy carbon crucible in a water-cooled sample chamber of an induction furnace. The sample was characterized by X-ray diffraction on both powder and single crystals. Zr5Ir2In4 crystallizes with a pronounced Lu5Ni2In4 type subcell, space group Pbam, a=1739.5(6), b=766.3(2), c=338.9(2) pm. Weak additional reflections force a doubling of the subcell c axis. The superstructure of Zr5Ir2In4 is of a new type: Pnma, a=1739.5(6), b=677.8(2), c=766.3(2) pm, wR2=0.0529, 1592 F2 values, and 60 variable parameters. The group-subgroup scheme for the klassengleiche symmetry reduction is presented. The formation of the superstructure is most likely due to a puckering effect (size of the iridium atoms). The crystal chemistry of Zr5Ir2In4 is briefly discussed.  相似文献   

6.
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   

7.
A new polymer azido-bridged copper(II) complex [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2] n (I) (En = ethylenediamine) has been synthesized and crystallography characterized. Complex I shows one-dimensional coordination polymeric structure based on a tetranuclear cluster unit [Cu4(En)21,1-N3)41,1,1-N3)21,3-N3)2], in which the azido ions display three different bridging modes.  相似文献   

8.
Two metal-organic coordination polymers [Cu(bpy)2(H2O)2](NO3)2·4.5C2H5OH (1) and [Cu2(bpy)(H2O)(L-pha) 2](NO3)2·H2O (2) (L-Hpha = L-phenylalanine, bpy = 4,4′-bipyridyl) are prepared by slow evaporation of an aqueous alcoholic solution of copper nitrate, L-phenylalanine, and 4,4′-bipyridyl. The structure and composition of the obtained compounds are determined by single crystal XRD. The framework of compound 1 is positively charged and forms two types of intersecting channels. Compound 2 is a homochiral metal-organic coordination polymer whose structure contains L-phenylalanine anions.  相似文献   

9.
 Oxo peroxo glycolato complexes of vanadium(V) (M 2[V2O2(O2)2(C2H2O3)2nH2O (n=0, 1; M=NBu4 + (1), K+ (2), NH4 + (3), Cs+ (4), NPr4 + (5)) as well as (NBu4)2[V2O4(C2H2O3)2]ċ H2O (6) have been prepared and characterized by spectroscopic methods. X-Ray structure analysis of 1 revealed the presence of dinuclear [V2O2(O2)2(C2H2O3)2]2− anions with a (chemical structure) bridging core and six coordinated vanadium(V) atoms in a distorted pentagonal pyramidal array.  相似文献   

10.

Abstract  

Thermolysis of cis-Fe(CO)4(SiCl3)2 results in the formation of the novel compound Fe2(CO)62-SiCl2)3, which was characterized by single crystal X-ray diffraction. Density functional theory calculations were carried out to elucidate possible reaction steps leading to the formation of Fe2(CO)6(SiCl2)3, including CO dissociation and chlorine abstraction by a SiCl3 radical generated from homolytic Fe–Si bond cleavage involving a singlet–triplet intersystem crossing.  相似文献   

11.
Two modifications of the new uranyl oxalate hydroxide dihydrate [UO2)2(C2O4)(OH)2(H2O)2] (1 and 2) and one form of the new uranyl oxalate hydroxide trihydrate [(UO2)2(C2O4)(OH)2(H2O)2]·H2O (3) were synthesized by hydrothermal methods and their structures determined from single-crystal X-ray diffraction data. The crystal structures were refined by full-matrix least-squares methods to agreement indices R(wR)=0.0372(0.0842) and 0.0267(0.0671) calculated for 1096 and 1167 unique observed reflections (I>2σ(I)), for α (1) and β (2) forms, respectively and to R(wR)=0.0301(0.0737) calculated for 2471 unique observed reflections (I>2σ(I)), for 3. The α-form of the dihydrate is triclinic, space group , Z=1, a=6.097(2), b=5.548(2), , α=89.353(5), β=94.387(5), γ=97.646(5)°, , β-form is monoclinic, space group C2/c, Z=4, a=12.180(3), b=8.223(2), , β=95.817(4), . The trihydrate is monoclinic, space group P21/c, Z=4, a=5.5095(12), b=15.195(3), , β=93.927(3), . In the three structures, the coordination of uranium atom is a pentagonal bipyramid composed of dioxo UO22+ cation perpendicular to five equatorial oxygen atoms belonging to one bidentate oxalate ion, one water molecule and two hydroxyl ions in trans configuration in 2 and in cis configuration in 1 and 3. The UO7 polyhedra are linked through hydroxyl oxygen atoms to form different structural building units, dimers [U2O10] obtained by edge-sharing in 1, chains [UO6] and tetramers [U4O26] built by corner-sharing in 2 and 3, respectively. These units are further connected by oxalate entities that act as bis-bidentate to form one-dimensional chains in 1 and bi-dimensional network in 2 and 3. These chains or layers are connected in frameworks by hydrogen-bond arrays.  相似文献   

12.
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   

13.
Two novel polynuclear complexes with methanoate anions and 3-hydroxypyridine ligands [Cu(μ-HCO2)2(3-pyOH)]n (1) and [Cu2(μ-HCO2)2(μ-3-pyOH)2(3-pyOH)2(HCO2)2]n (2), respectively, were synthesized and characterized. The central copper atom in 1 is surrounded by four methanoates and a 3-pyOH molecule, forming a square-pyramidal CuO3NO chromophore. All the methanoates are bidentate and serve as bridges between the adjacent copper ions via syn-anti and anti–anti coordination. The basal square coordination axes are formed by O(syn), N(3-pyOH) (1.974(2), 2.016(2) Å) and O(anti), O(anti) (1.945(2), 1.960(2) Å), while the third O(anti) (2.247(2) Å) is on the top of the pyramid. A ferromagnetic transition with an exchange constant 2J/kB = 9.2 cm−1 is found for 1 below 20 K. This interaction probably takes place through two syn-anti methanoates extended in a chain through the 2D structure. On the other hand, two monoatomic Cu–O–Cu intra-dinuclear asymmetric (1.986(2), 2.415(2) Å) bridges of two methanoates in [Cu2(HCO2)4(3-pyOH)4] (2) are present. An elongated distorted octahedral coordination sphere around each copper(II) atom is completed by an additional monodentate terminal methanoate (1.975(2) Å), two N-coordinated 3-pyOH (2.005(2), 2.002(2) Å) and the third weakly O-coordinated 3-pyOH (2.732(2) Å). Although a shorter Cu?Cu distance is noticed in 2 than in 1 (4.690(1) Å 1, 3.442(1) Å 2), much weaker ferromagnetism is found in 2.  相似文献   

14.
A two-dimensional layered manganese(Ⅱ) pyrophosphate, [NH4]2[Mn3(P2O7)2(H2O)2] (1), has been synthesized hydrothermally. Its structure is determined by single-crystal X-ray diffraction analysis. Its structure is built up by MnO6 octahedra and P2O7 units, with ammonium NH4+ cations residing in the interlayer regions. The manganese pyrophosphate layer consists of infinite chains of cis and trans edge sharing MnO6 octahedra linked by P2O7 units. Magnetic susceptibility measurements show that this compound exhibits ferrimagnetic-like ordering below 3.2 K. Further study shows that there are two possible superexchange pathways via the oxygen anions in Mn2+ ions. Owing to the different bridging modes of O2-, the competition between ferromagnetic interactions and antiferromagnetic interactions in Mn2+ ions results in the ferrimagnetic behavior of 1.  相似文献   

15.
Reactions of [(dtc)2Mo2(S)2(μ-S)2] with one or two equivalents of CuBr in CH2Cl2 afforded two new heterobimetallic sulfide clusters, [(dtc)2Mo23-S)(μ-S)3(CuBr)] (1) and [(dtc)2Mo23-S)4(CuBr)2] (2). Both compounds were characterized by elemental analysis, IR, UV-vis and X-ray analysis. Compound 1 contains a butterfly-shaped Mo2S4Cu core in which one CuBr unit is coordinated by one bridging S and two terminal S atoms of the [(dtc)2Mo2(S)2(μ-S)2] moiety. In the structure of 2, one [(dtc)2Mo2(S)2(μ-S)2] moiety and two CuBr units are held together by six Cu-μ3-S bonds, forming a cubane-like Mo2S4Cu2 core.  相似文献   

16.
Methods for the synthesis of trans-diammino complexes [RuNO(NH3)2(NO2)2(OH)] (I) and [RuNO(NH3)2(H2O)(NO3)2](NO3)·H2O (II) are suggested. The compounds were studied by IR spectroscopy and X-ray phase and X-ray structural analyses. Crystal data: space group P-1; a = 6.2328(2) ?, b = 11.0488(3) ?, c = 11.0981(4) ?, α = 71.942(1)°, β = 83.291(1)°, γ = 86.877(1)° (I); space group P21; a = 6.6290(2) ?, b = 13.4389(5) ?, c = 7.0180(2) ?, β 114.281(1)° (II). Complex II readily lost some part of crystal water on storage in open air. Original Russian Text Copyright ? 2009 by M. A. Il’in, E. V. Kabin, V. A. Emel’yanov, I. A. Baidina, and V. A. Vorob’yov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 341–348, March–April, 2009.  相似文献   

17.
利用微波技术合成了配合物[Gd2(Gly)6(H2O)4](ClO4)6(H2O)5, 进行了化学成分分析、红外表征和热重分析. 应用X衍射仪测定其晶体结构, 该晶体为一维链结构, 属三斜晶系, P 空间群, 晶胞参数: a=1.1569(17) nm, b=1.4138(2) nm, c=1.5642(2) nm, α=96.910(2)°, β=102.735(2)°, γ=105.512(2)°, V=2.3606(6) nm3, Z=2, Dc=2.144 g•cm-3. 采用精密溶解-反应量热计, 通过设计热化学循环, 计算出了该配合物的标准摩尔生成焓为 -(7960.73±3.23) kJ•mol-1.  相似文献   

18.
标题配合物M=1892.01,单斜晶系,空间群P21/c, a=1.2975(3) nm, b=2.6591(9) nm, c=1.2118(3) nm, β=96.95(1)°, Z=2, Dc=1.577 g/cm3, T=293(2)K。最终的偏离因子R=0.0583。该配合物以二聚体形式存在,通过其中的桥联羧基形成了双核分子。该分子中羧基具有桥联双齿、桥联三齿和单齿三种配位模式,Eu-Eu之间的距离为0.4019(1) nm。在77K下测得配合物中Eu(Ⅲ)离子仅有一种格位。 5D07FJ(J=0~2)跃迁光谱说明Eu(Ⅲ)离子格位具有C2对称性。  相似文献   

19.
Two new dicyanamide coordination polymers, {Mn(dmpz)[N(CN)2]2}2 (1) and {Cu(dmpz)[N(CN)2]2}2 (2)(dmpz=3,5-dimethylpyrazole), were synthesized and characterized by single crystal X-ray diffraction analysis and IR spectroscopy. In 1 and 2 the metal ions have two different coordination modes, where one is coordinated to four dicyanamide anions and two monodentate dmpz molecules to form a slightly distorted octahedral geometry, while the other adopts octahedral geometry, surrounded by four nitrile N atoms and two amide N atoms of the dicyanamide anions. Both complexes contain two alternating chains that are parallel to each other.  相似文献   

20.
四核铁配合物[Fe4(NTB)42-O)24-Suc)](ClO4)6与DNA具有较强的结合作用,结合常数kb达(5.9±0.4)×105 L·mol-1。该多核铁配合物由水解途径促进DNA断裂,在酸性及低离子浓度条件下的促进作用较为显著。动力学分析表明DNA水解没有明显的序列选择性,质粒DNA从超螺旋转变为切口形式符合饱和酶动力学规律,饱和速率常数ksat=0.014 min-1。  相似文献   

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