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1.
Synthesis and crystal structures of two new compounds, K2[CrCl5(H2O)] ( I ) and (NH4)2[CrCl5(H2O)] ( II ) are reported. Both compounds were prepared from chromium(VI) salts by two different methods and reaction pathways of these syntheses are suggested. The crystal structures of these two aquapentachlorochromates(III) have been determined from three dimensional X‐ray data collected at low temperature, 173 K. The two structures are isomorphous and their unit cell dimensions are quite similar. They are orthorhombic, space groups Pnma, with Z = 4. Both structures are composed of [CrCl5(H2O)]2? units held together by the counterion framework. The coordination around the chromium ion deviates from a regular octahedron due to the shorter equatorial chromium‐oxygen bond.  相似文献   

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采用熔融硼酸法合成了一种具有层状结构的新型水合稀土多硼酸盐, La[B5O8(OH)(H2O)]NO3•2H2O, 并利用单晶X射线衍射技术确定了它的结构. 它属于单斜晶系, P21/n空间群. 其基本构建单元 (fundamental building block, 简称FBB)是由三个BO4和两个BO3基团所构成的一个双三元环[B5O12]基团. 结构中每一个FBB通过共顶点氧原子与周围四个同样的单元连接成具有九元环窗口的二维[B5O10]层, La3+位于九元环中心附近. [B5O10]层沿着b方向进行堆积, 硝酸根离子和结构中部分结晶水分子位于相邻的[B5O10]层之间.  相似文献   

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Structures and Thermal Decomposition of enH2(H3O)[AlF6] and enH2[AlF5(H2O)] By precipitation with ethylene diamine (en) from a hydrofluoric acid solution of aluminium enH2(H3O)[AlF6] is formed. It crystallizes in the orthorhombic space group Pnma, a = 1084.9(1), b = 1079.4(1), c = 682.0(1) pm, R = 0.032. H3O+ cations and [AlF6]3– anions are connected via strong H bonds to layers which are further linked to a 3 D network by H bonds from the enH22+ cations. By recrystallization from water or precipitation from a less acid solution enH2[AlF5(H2O)] is formed, which crystallizes monoclinic in the space group P21 (a = 660.0(1), b = 563.5(1), c = 994.4(2) pm, β = 98.44(3)°, R = 0.029). The [AlF5(H2O)]2– anions are linked by strong O–H…F bonding to form ‘einer-double chains' interconnected again via the enH22+ cations to a 3 D framework. Thermoanalytical investigations show that enH2[AlF5(H2O)], by loss of water above 150 °C, as well as enH2(H3O)[AlF6], by loss of water and HF above 120 °C, transform to enH2AlF5. The subsequent decomposition goes over NH4+ containing intermediates towards β-AlF3. Before decomposition the oxonium fluoroaluminate reveals a reversible phase transition at 99 °C.  相似文献   

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GdⅢ的配合物常被用作MRI造影剂[1,2]. GdⅢ的离子半径和电子结构分别为0.107 8 nm和高自旋f 7, 理论预测应与氨基多羧酸类配体形成稳定的九配位配合物[3~5]. 为证实理论预测并在此基础上寻找合适的可用于定向修饰的配体以及为提高GdⅢ配合物的脂溶性使其具有更好的细胞渗透性, 选择四齿配体nta和含有脂环烃的六齿配体Cydta分别合成了GdⅢ的配合物, 并测定了它们的分子结构. 结果显示, GdⅢ与nta形成九配位配合物, GdⅢ与Cydta形成八配位配合物.  相似文献   

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The title compound, namely octa­aqua­ytterbium(III) aqua­nona­chloro­tricadmate(II) hexa­hydrate, [Yb(H2O)8][Cd3Cl9(H2O)]·6H2O, was prepared by evaporation at 278 K from an aqueous solution of the ternary system YbCl3–CdCl2–H2O and was characterized by elemental chemical analysis and by X‐ray powder and single‐crystal diffraction studies. The crystal structure can be viewed as being built from layers of double chains of CdCl6 and CdCl5(H2O) octahedra separated by antiprismatic [Yb(H2O)8]3+ cations. The stabilization of the structure is ensured by O—H⋯O and O—H⋯Cl hydrogen bonds. A comparison with the structures of SrCd2Cl6·8H2O and CeCd4Cl11·13H2O is presented.  相似文献   

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On the Thermal Decomposition of (NH4)2[FeF5(H2O)] on Quasi-Isobaric Conditions The thermal decomposition of (NH4)2[FeF5(H2O)] was investigated by thermal and X-ray analysis. Quasi-isobaric conditions are realized by using a special crucible which guaranteed a pressure of the gaseous products of 70 kPa. In dependence on the partial pressure α- or β-(NH4)2FeF5 were formed during dehydration. Further intermediate products are NH4FeF4, (NH4)1?xFeF4?x, and (NH4)yFeF3 with x = 0.15–0.20 and y = 0.12–0.15. Structural relations between these phases are discussed and comparable considerations to the Al system were made.  相似文献   

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Two new complexes, [Mn2(L)2(H2bta)2(H2O)]n ( 1 ) and [Cu2(L)(H2bta)0.5(H2O)]n ( 2 ) (H4bta=1,2,4,5‐benzene‐tetracarboxylic acid, L=imidazo[4,5‐f][1,10]phenathroline) were prepared under hydrothermal conditions and their structures determined by single‐crystal X‐ray diffration. The X‐ray diffraction reveals that complex 1 , consisting of two crystallographically independent fragments A1 and A2, displays an interesting 3D supramolecular network constructed with ABAB sequence through hydrogen bonding interactions. In complex 2 , the copper atoms connected by the H2bta2? ligands, the chains also are assembled into a 3D honeycomb configuration network formed by moleculars and aromatic π‐π stacking interactions.  相似文献   

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Crystal Structure of (NMe4)2[Re3Br11(H2O)] [Re3Br9(H2O)3](H2O)2 . (NMe4)2[Re3Br11(H2O)] [Re3Br9(H2O)3](H2O)2 crystallizes from hydrobromic acid solution of Re3Br9 · 2 H2O and NMe4Br at 0 – 5°C. The crystal structure (monoclinic; P21/m (Nr. 11); a = 967.9(3); b = 1 529.7(4); c = 1 710.9(4) pm; β = 91.66(2)°; Z = 2; R = 0.113; Rw = 0.068) has been determined from four-circle diffractometer data. The structure contains two different cluster units of trivalent rhenium, isolated anionic [Re3Br11(H2O)]2? units and neutral cluster units that are connected through crystal water molecules to chains{[Re3Br9(H2O)3](H2O)2}.  相似文献   

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利用水热法首次合成了具有两种配位环境Cd原子的新型杂多蓝化合物[NH3(CH2)2NH3]5[Cd(H2O)][CdMoV12O30(HPO4)6(H2PO4)2]·5H2O.通过元素分析、ICP、TG和X射线单晶衍射确定了其组成,使用IR和EPR进行了结构表征.通过N2吸附脱附测定了比表面积和孔径,为催化研究提供了基础数据.结果表明:该晶体为三斜晶系,P-1空间群;晶胞参数a=1.200 2(2)nm,b=1.465 1(3)nm,c=2.119 2(4)nm,V=3.5642(12)nm3,β=83.01(3)°,Z=2,F(000)=293 2,R1=0.0300,wR3=0.071 6.  相似文献   

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The single crystals of (C2H7N4O)2[UO2(C2O4)2(H2O)] were studied by X-ray diffraction. The crystals are monoclinic, space group Pn, Z = 2, unit cell parameters: a = 9.4123(2) Å, b = 8.4591(2) Å, c = 11.8740(3) Å, β = 105.500(10)°, V = 911.02(4) Å3. The main structural units of the crystals of I are islet complex groups [UO2(C2O4)2(H2O)]2? corresponding to the crystal chemical group AB 2 01 M1 (A = UO UO 2 2+ , B01 = C2O 4 2? , M = H2O) of uranyl complexes. Uranium-containing mononuclear complexes are connected into a three-dimensional framework through the electrostatic interactions and hydrogen bonding system involving carbamyolguanidinium ions.  相似文献   

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Conclusions Tetracyclopentadienyldizirconoxanedibenyl was synthesized by the reaction of benzylmagnesium chloride with (-Cp2ZrCl)2O. The complex is an efficient benzylating agent, and it alkylates HgCl2 to dibenzylmercury.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1676–1678, July, 1978.The authors express their gratitude to D. V. Zagorevskii for taking the mass spectra.  相似文献   

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Diaquabis[dihydrogen 1‐hydroxy‐2‐(imidazol‐3‐ium‐1‐yl)ethylidene‐1,1‐diphosphonato‐κ2O,O′]magnesium(II), [Mg(C5H9N2O7P2)2(H2O)2], consists of isolated dimeric units built up around an inversion centre and tightly interconnected by hydrogen bonding. The MgII cation resides at the symmetry centre, surrounded in a rather regular octahedral geometry by two chelating zwitterionic zoledronate(1−) [or dihydrogen 1‐hydroxy‐2‐(imidazol‐3‐ium‐1‐yl)ethylidene‐1,1‐diphosphonate] anions and two water molecules, in a pattern already found in a few reported isologues where the anion is bound to transition metals (Co, Zn and Ni). catena‐Poly[[aquacalcium(II)]‐μ3‐[hydrogen 1‐hydroxy‐2‐(imidazol‐3‐ium‐1‐yl)ethylidene‐1,1‐diphosphonato]‐κ5O:O,O′:O′,O′′], [Ca(C5H8N2O7P2)(H2O)]n, consists instead of a CaII cation in a general position, a zwitterionic zoledronate(2−) anion and a coordinated water molecule. The geometry around the CaII atom, provided by six bisphosphonate O atoms and one water ligand, is that of a pentagonal bipyramid with the CaII atom displaced by 0.19 Å out of the equatorial plane. These CaII coordination polyhedra are `threaded' by the 21 axis so that successive polyhedra share edges of their pentagonal basal planes. This results in a strongly coupled rhomboidal Ca2–O2 chain which runs along [010]. These chains are in turn linked by an apical O atom from a –PO3 group in a neighbouring chain. This O‐atom, shared between chains, generates strong covalently bonded planar arrays parallel to (100). Finally, these sheets are linked by hydrogen bonds into a three‐dimensional structure. Owing to the extreme affinity of zoledronic acid for bone tissue, in general, and with calcium as one of the major constituents of bone, it is expected that this structure will be useful in modelling some of the biologically interesting processes in which the drug takes part.  相似文献   

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余坚  郝志峰  张耀方  余林 《合成化学》2007,15(5):566-569
N-苯基亚氨基二乙酸(H2L),Mn(Ⅱ)和2,2'-联吡啶(2,2'-bipy)在50%甲醇中组装得标题配合物[MnL(2,2'-bipy)(H2O)]·2H2O(1),其结构经IR,元素分析和X-射线单晶衍射表征.1属单斜晶系,空间群P2(1)/n,晶胞参数:a=0.885 9(3)nm,b=1.826 9(6)nm,c=1.385 7(5)nm,β=106.200(6)°,V=2.153 6(13)nm3,Z=4,F(000)=980,Dc=1.457 Mg·m-3.在1的晶体结构中,Mn(Ⅱ)为六配位的畸变八面体构型,其中2,2'-bipy的2个氮原子和羧基的2个氧原子位于赤道平面,L的氮原子和一个配位水分子处于轴向位置.1分子之间存在的氢键与π-π芳香堆积作用将其连接成三维超分子结构.  相似文献   

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Research on Chemical Intermediates - A novel six-coordinate complex of Zr(IV) with curcumin ligand was synthesized and characterized by thermogravimetric analysis, elemental analysis and...  相似文献   

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Russian Journal of Coordination Chemistry - The crystal structure of ammonium pentachloroaquaferrate (NH4)2[FeCl5(H2O)] is refined (CIF file CCDC no. 1831198). Compounds...  相似文献   

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