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K2Zn3O4 and Rb2Zn3O4, Oxozincates with Framework Structure For the first time single crystals of K2Zn3O4 were obtained by heating mixtures of the binary oxides (K: Zn = 2.2:3) in sealed Ag- or Pt-capsules at 800°C (5 w). Powder of this colourless and moisture-sensitive oxide was prepared analogously at 500°C. It crystallizes monoclinic, space group C2/c with a = 1482.7(2), b = 637.3(1), c = 571,9(1) pm, β = 102.79(1)°, Z = 4, dx = 4.265 g/cm3, dpyk = 4.00 g/cm3. The crystal structure was determined from four-circle diffractometer data (MoKα, 730 unique hkl) and refined to R = 5.9%, Rw = 6.4%. It shows a Zn3O4 framework which consists of SiS2-like chains [ZnO4/2] connected by puckered layers of [ZnO3/3]. The crystal structure can be derived from a cubic closet packing of O2? and K+. Effective Coordination Numbers and the Madelung Part of Lattice Energy (MAPLE) are calculated. Rb2Zn3O4 was prepared from the binary oxides at 400°C (colourless hygroscopic powder). According to powder data it crystallizes isostructural to K2Zn3O4 with a = 1523.5(4), b = 649.8(2), c = 574.0(2) pm, β = 101.43(3)°, Z = 4, dx = 5.141 g/cm3, dpyk = 5.20 g/cm3.  相似文献   

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A New Synthesis of DL -Armentomycin and Related 2-Amino-4-polyhalobutyric Acids An efficient method for the synthesis of 2-amino-4-halobutyric acids 2 starting from the corresponding ethyl 2,4-polyhalobutyrates 1 is presented (s. Scheme 1). The method is illustrated by a high yield synthesis of the known antibiotic DL -armentomycin (= 2-amino-4,4-dichlorobutyric acid; 2a ).  相似文献   

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[Me3SnVO3] and [(Me2Sn)4V2O9], two Organotin Vanadates with Novel 3D Network Structures Two new organotin vanadates [Me3SnVO3] ( 1 ) and [(Me2Sn)4V2O9] ( 2 ) have been prepared by the reaction of NH4VO3 with Me3SnBr and Me2SnBr2 resp. in agar gel. The structures of 1 and 2 have been determined by x‐ray crystallography at 220 K. 1 crystallizes monoclinic in the space group P21/c with a = 1335.6(2), b = 1144.4(2), c = 1118.8(2) pm, β = 113.54(2)°. 2 crystallizes orthorhombic in the space group Pnnm with a = 1257.6(2), b = 1345.4(2), c = 1323.1(1) pm. 1 consists of infinite metavanadate chains which are linked by Me3Sn+ cations. 2 exhibits a complex 3D‐ network structure with VO4 tetrahedra, Me2SnO3 trigonal bipyramides and Me2SnO4 octahedra linked by common oxygen atoms.  相似文献   

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Thio- and Selenomercurates(II). K6[HgS4], K6[HgSe4], Rb6[HgS4] and Rb6[HgSe4] We prepared by annealing intimate mixture of pure samples of K2S, K2Se, Rb2S, and Rb2Se with HgS or HgSe [360–380°C, 7d, Duran-glass-seal with Argon] with hexagonal Na6ZnO4 isotypic new mercurates: K6[HgS4] [bright citronic yellow a = 9.985, c = 7.652 Å], K6[HgSe4] [light orange yellow a = 10.36, c = 7.883 Å], Rb6[HgS4] [bright yellow a = 10.34, c = 7.942 Å], Rb6[HgSe4] [orange-red a = 10.72, c = 8.192 Å]. The crystal structure of K6 Hgs4 is elucidated by using diffractometer data of single crystals: P63mc, C46v, it is R = 6.6% for 304 reflexes [h k o–h k 4, anisotropic refinement MoKα]; for position and parameters see text d = 2.835, dpyk = 2.99 g · cm?3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.  相似文献   

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Pseudohalogeno Metal Compounds. LXXVIII. Structures of Planar and Tetrahedral Tetrafulminato Metal Complexes: [N(C3H7)4]2 [Ni(CNO)4], [N(C3H7)4]2 [Pt(CNO)4], and [N(C3H7)4]2 [Zn(CNO)4] The crystals contain the tetrafulminatometallates of an ideal square planar structure ([Ni(CNO)4]2–, [Pt(CNO)4]2–) with D4h symmetry at the nickel and platinum atom and a tetrahedron ([Zn(CNO)4]2–) with perfect Td symmetry at the zinc atom and with linear C≡N–O ligands. The metal carbon bonds (Ni–C: 187 pm, Pt–C: 200 pm, Zn–C: 201 pm) of the metal fulminates are very close to those of the corresponding cyano complexes. In the crystals the anions ([Ni(CNO)4]2–, [Pt(CNO)4]2–, [Zn(CNO)4]2–) are separated by the cations ([N(C3H7)4]+) which explains the thermal stability of these compounds.  相似文献   

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About Selenidostannates. I Synthesis, Structure, and Properties of [Sn2Se6]4–, [Sn4Se10]4–, and [Sn3Se7]2– The selenidostannates [(C4H9)2NH2]4Sn2Se6 · H2O ( I ), [(C4H9)2NH2]4Sn4Se10 · 2 H2O ( II ) und [(C3H7)3NH]2Sn3Se7 ( III ) were prepared by hydrothermal syntheses from the elements and the amines. I crystallizes in the monoclinic spacegroup P21/n (a = 1262.9(3) pm, b = 1851.3(4) pm, c = 2305.2(4) pm, β = 104.13(3)° and Z = 4). The [Sn2Se6]4– anion consists of two edge‐sharing tetrahedra. II crystallizes in the orthorhombic spacegroup Pna21 (a = 2080.3(4) pm, b = 1308.2(3) pm, c = 2263.5(5) pm and Z = 4). The anion is formed from four SnSe4 tetrahedra which are joined by common corners to the adamantane cage [Sn4Se10]4–. III crystallizes in the orthorhombic spacegroup Pbcn (a = 1371.1(3) pm, b = 2285.4(5) pm, c = 2194.7(4) pm and Z = 8). The anion is a chain, built from edge‐sharing [Sn3Se5Se4/2]2– units, in which two corner sharing tetrahedra are connected to a trigonal bipyramid by an edge of one and a corner of the other tetrahedron. The results of the TG/DSC measurements and of temperature dependent X‐ray diffractograms reveal that I and II decompose at first by release of minor quantities of triethylammonium to compounds with layer structure and larger cell dimensions. At still higher temperature the rest of triethylammonium and H2Se is evolved, leaving SnSe2 and Se in the bulk. The former decomposes partially at the highest temperature to SnSe. In the measurements of III the complex intermediate compound was not observed. III decomposes directly to SnSe2.  相似文献   

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SeBr3[AlBr4] and TeI3[AlI4] – two further Compounds in the SCl3[AlCl4] Structure Type The reaction of SeBr4 and AlBr3 in a closed glass ampoule at 150°C yields quantitatively SeBr3[AlBr4] in form of yellow moisture sensitive crystals. From Te, two equivalents of I2, and AlI3 one obtains TeI3[AlI4] in form of dark red, moisture sensitive crystals. Both compounds crystallize monoclinic in the space group Pc (SeBr3[AlBr4]: a = 670.7(7) pm, b = 663.9(5) pm, c = 1 428.6(2) pm, β = 101.21(9)°, TeI3[AlI4]: a = 731.9(1) pm, b = 730.8(1) pm, c = 1 565.5(3) pm, β = 102.01(2)°). They are isotypic and have the SCl3[AlCl4] structure type. The structures are built of tetrahedral AlX4? ions and of pyramidal EX3+ ions (E = S, Se, Te; X = Cl, Br, I). The chalcogen atoms are additionally coordinated by halogen atoms of surrounding AlX4? ions, corresponding to a strongly distorted octahedral coordination EX3+3.  相似文献   

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News on K2[MnF6], Rb2[MnF6], and Cs2[MnF6] Cs2[MnF6] (a = 8.972 Å) and Rb2[MnF6] (a = 8.531 Å) as well as this with K2[MnF6] (a = 8.221 Å and hexagonal a = 5.722, c = 9.331 Å) form mixed crystals of the K2PtCl6 type of structure. Calculations of the Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, lead contrary to former assumptions to distances Mn? F of about 1.86 Å (CN 6).  相似文献   

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Alkoxo Compounds of Iron(III): Syntheses and Characterization of [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] and [N(nBu)4]2[Fe6OCl6(OMe)12] The reaction of iron(III)chloride in diethylether with sodium tert‐butylat yielded the homoleptic dimeric tert‐‐butoxide Fe2(OtBu)6 ( 1 ). The chloro‐derivatives [Fe2Cl2(OtBu)4] ( 2 ), and [Fe2Cl4(OtBu)2] ( 3 ) could be synthesized by ligand exchange between 1 and iron(III)chloride. Each of the molecules 1 , 2 , and 3 consists of two edge‐sharing tetrahedrons, with two tert‐butoxo‐groups as μ2‐bridging ligands. For the synthesis of the alkoxides 1 , 2 , and 3 diethylether plays an important role. In the first step the dietherate of iron(III)chloride FeCl3(OEt2)2 ( 4 ) is formed. The reaction of iron(III)chloride with tetrabutylammonium methoxide in methanol results in the formation of a tetrabutylammonium methoxo‐chloro‐oxo‐hexairon cluster [N(nBu)4]2[Fe6OCl6(OMe)12] ( 5 ). Crystal structure data: 1 , triclinic, P1¯, a = 9.882(2) Å, b = 10.523(2) Å, c = 15.972(3) Å, α = 73.986(4)°, β = 88.713(4)°, γ = 87.145(4)°, V = 1594.4(5) Å3, Z = 2, dc = 1.146 gcm—1, R1 = 0.044; 2 , monoclinic, P21/n, a = 11.134(2) Å, b = 10.141(2) Å, c = 12.152(2) Å und β = 114.157(3)°, V = 1251.8(4) Å3, Z = 2, dc = 1.377 gcm—1, R1 = 0.0581; 3 , monoclinic, P21/n, a = 6.527(2) Å, b = 11.744(2) Å, c = 10.623(2), β = 96.644(3)°, V = 808.8(2) Å3, Z = 2, dc = 1.641 gcm—1, R1 = 0.0174; 4 , orthorhombic, Iba2, a = 23.266(5) Å, b = 9.541(2) Å, c = 12.867(3) Å, V = 2856(2) Å3, Z = 8, dc = 1.444 gcm—1, R1 = 0.0208; 5 , trigonal, P31, a = 13.945(2) Å, c = 30.011(6) Å, V = 5054(2) Å3, Z = 6, dc = 1.401 gcm—1; Rc = 0.0494.  相似文献   

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Polyol Metal Complexes. XIII. Na2[Be(C4H6O3)2] · 5H2O and Na2[Pb(C4H6O3)2] · 3H2O – Two Homoleptic Bis Polyolato Metallates with Beryllium and with Lead Na2[Be(C4H6O3)2] · 5H2O ( 1 ) and Na2[Pb(C4H6O3)2] · 3H2O ( 2 ) crystallize from concentrated, alkaline aqueous solutions. The polyol anhydroerythritol is deprotonated twice in the mononuclear, homoleptic complex anions. The preference of beryllium for the binding of cis-furanoid diols is shown. In 2 , a stereochemically active lone pair at the central atom is the reason for the construction of low dimensional aggregates from three plumbate and three sodium ions.  相似文献   

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The structure of [Co(H2O)4][VO(PO4)]2 is composed of [VO(PO4)] layers and interlayer tetrahydrated Co2+ ions. Alternating VO5 square pyramids and PO4 tetrahedra share O‐atom vertices, thus forming the vanadyl phosphate layers. Two vanadyl oxo groups from neighbouring layers are coordinated to each Co atom in a trans fashion, with Co—O distances of 2.157 (4) Å, thus generating a three‐dimensional framework structure.  相似文献   

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由于在电学、磁学、光学、吸附、离子交换和催化等领域具有潜在的应用价值,具有开放骨架结构的金属磷酸盐的合成一直受到人们的广泛关注。在这些磷酸盐微孔化合物中,磷酸锌晶体是拓扑结构最为丰富的一种犤1犦。自从Stucky等犤2犦报道具有SOD、Li-ABW、FAU等已知结构磷酸锌的合成以来,已经有近百种具有0-D犤3,4犦,1-D犤5,6犦,2-D犤7~9犦,3-D犤10~13犦结构的磷酸锌被成功地合成出来。其中令人瞩目的是具有螺旋孔道的手性磷酸锌犤14犦以及具有二十四元环孔道的两种微孔磷酸锌化合物犤15,16犦的合成。这些化合物大多是采用水热技术以有…  相似文献   

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A process for the preparation of alkyl chloromethylphosphonites, ClCH2P(OR)2 (R = Et, Bu), diethyl β-chloroethylphosphonite, ClCH2CH2P(OEt)2, and their conversion to polyphosphinates with the back-bone structures ? [? CH2PO2R? ]? x and ? [? CH2CH2P(O2R)? ]? x, respectively, by an Arbuzov type reaction is described. Hydrolysis to the corresponding polyphosphinic acids is effected by refluxing the esters with conc. HCl for extended periods. The polyphosphinic acid with structure V is an excellent chelating agent for Ca ions.  相似文献   

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