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1.
Li B  Corbett JD 《Inorganic chemistry》2002,41(15):3944-3949
This phase was discovered following direct fusion of the elements in welded Nb tubes at 550 degrees C and equilibration at 300 degrees C for 1 week. Single-crystal X-ray diffraction analysis reveals that KNa(3)In(9) crystallizes in an orthorhombic system (Cmca, Z = 8, a = 9.960(1) A, b =16.564(2) A, c = 17.530(2) A, 23 degrees C). The structure contains a three-dimensional indium network built of layers of empty In(12) icosahedra that are each 12-bonded and interconnected by 4-bonded indium atoms that also form zigzag chains. All cations bridge between cluster faces or edges, and their mixed sizes appear critical to the stability of this particular structure, which does not occur in either binary system. Both empirical electron counting and EHTB band structure calculations on the macroanion indicate that the bonding in this structure is closed-shell, whereas resistivity and magnetic susceptibility measures show that the compound is a moderately poor metal.  相似文献   

2.
A new three-dimensional hydroxide-arsenate compound called compound 2 has been synthesized by heating (in air) of the sarkinite phase, Mn(2)(OH)AsO(4) (compound 1), with temperature and time control. The crystal structure of this high-temperature compound has been solved by Patterson-function direct methods. A relevant feature of this new material is that it is actually the first member of the adamite-type family with mixed-valence manganese(II,III) and electronic conductivity. Crystal data: a = 6.7367(5) ?, b = 7.5220(6) ?, c = 9.8117(6) ?, α = 92.410(4)°, β = 109.840(4)°, γ = 115.946(4)°, P1?. The unit cell content derived from Rietveld refinement is Mn(8)(O(4)H(x))(AsO(4))(4). Its framework, projected along [111], is characterized by rings of eight Mn atoms with the OH(-)/O(2-) inside the rings. These rings form an almost perfect hexagonal arrangement with the AsO(4) groups placed in between. Bond-valence analysis indicates both partial deprotonation (x ? 3) and the presence of Mn in two different oxidation states (II and III), which is consistent with the electronic conductivity above 300 °C from electrochemical measurements. The electron paramagnetic resonance spectra of compound 1 and of its high-temperature form compound 2 show the presence of antiferromagnetic interactions with stronger magnetic coupling for the high-temperature phase. Magnetization measurements of room-temperature compound 1 show a complex magnetic behavior, with a three-dimensional antiferromagnetic ordering and magnetic anomalies at low temperatures, whereas for compound 2, an ordered state is not reached. Magnetostructural correlations indicate that superexchange interactions via oxygen are present in both compounds. The values of the magnetic exchange pathways [Mn-O-Mn] are characteristic of antiferromagnetic couplings. Notwithstanding, the existence of competition between different magnetic interactions through superexchange pathways can cause the complex magnetic behavior of compound 1. The loss of three-dimensional magnetic ordering by heating of compound 1 could well be based on the presence of Mn(3+) ions (d(4)) in compound 2.  相似文献   

3.
Hung LI  Wang SL  Kao HM  Lii KH 《Inorganic chemistry》2007,46(8):3301-3305
Two novel indium silicates, K5In3Si7O21 (1) and K4In2Si8O21 (2), have been synthesized by a flux-growth method and characterized by single-crystal X-ray diffraction. The structure of 1 consists of siebener single chains of corner-sharing SiO4 tetrahedra running along the b axis linked via corner-sharing by In2O9 face-sharing octahedral dimers and InO5 trigonal bipyramids to form a 3D framework. The structure of 2 consists of a 3D silicate framework containing 6- and 14-ring channels. InO5 square pyramids are located within the 14-ring channels sharing corners with the silicate framework. The solid-state 29Si MAS NMR spectrum of compound 1 was recorded; it shows the influence of the indium atoms in the second coordination sphere of the silicon on the chemical shift. Crystal data: 1, orthorhombic, Pna21 (No. 33), a = 12.4914(3) A, b = 16.8849(3) A, c = 10.2275(2) A, V = 2157.1(1) A3 and Z = 4; 2, monoclinic, P21/n (No. 14), a = 8.4041(3) A, b = 11.4919(4) A, c = 10.4841(3) A, beta = 90.478(2) degrees , V = 1012.5(1) A3 and Z = 2.  相似文献   

4.
Li B  Corbett JD 《Inorganic chemistry》2006,45(7):2960-2964
The cluster compounds KNa3In9 [K2Na6(In12)(In)6] and Na2In [(Na)8(In4)], which contain In12 icosahedra interbridged by 4-bonded In atoms and isolated In4 tetrahedra, respectively, both have classical closed-shell electronic configurations but show metallic transport properties. These contrasts have been studied by means of first-principles density functional methods (LMTO-ASA). Several bands cross the Fermi level in both compounds, consistent with their metallic properties. In KNa3In9, the metal atom framework alone is sufficient to generate a metallic characteristic. The alkali-metal s and indium p orbitals mix considerably in both phases, providing for substantial covalent contributions to their stabilities as well as bands crossing Ef. The participation of Na atoms in the 3D bonding networks is more striking in cation-richer Na2In than in KNa3In9.  相似文献   

5.
The title compound, [InCl(C4H5NO4)]n, has been synthesized via the hydrothermal method and characterized by IR, elemental analysis, UV-Vis-Nir spectra and single-crystal X-ray diffraction analysis. Single-crystal X-ray analyses show that it is a carboxylate-bridged two-dimensional layer network indium(III) polymer, catena-poly[[chloroindium(III)]-μ-(iminodiacetate к4N,O,O':O':O'']. The crystal is of orthorhombic system, space group Pnma with a = 13.5970(13), b = 8.7671(10), c = 6.0427(5), C4H5ClInNO4, Mr = 281.36, V = 720.33(12)3, Z = 4, Dc = 2.594 g/cm3, F(000) = 536, μ = 3.613 mm-1, R = 0.0245 and wR = 0.0570. The In(III) ion exhibits an approximately octahedral InClNO4 coordination environment, with the two O donor atoms of iminodiacetate and two O atoms belonging to the carboxylate group of two adjacent iminodiacetates occupying the basal positions, and the chlorine ion and one nitrogen atom of iminodiacetate in the apical sites. Carboxylate groups are mutually cis oriented, and each syn-anti carboxylate group bridges two indium(III) ions via two different basal positions, resulting in the formation of a 2-D network with rhombus (4, 4) grids. Each rhombus grid unit is formed from four indium atoms and four iminodiacetate units with the diagonal lengths of 8.767(1) and 6.043(1).  相似文献   

6.
A mercury pnictide halide semiconductor Hg19As10Br18(1) has been prepared by the solid-state reaction and structurally characterized by single-crystal X-ray diffraction analysis.Compound 1 crystallizes in triclinic,space group P with a = 11.262(4),b = 11.352(4),c = 12.309(5) ,α = 105.724(2),β = 105.788(4),γ = 109.0780(10)° and V = 1314.3(8) 3.The structure of 1 is composed of parallel perovskite-like layers bridged by the linearly coordinated Br atoms to form a three-dimensional framework.The optical properties were investigated in terms of the diffuse reflectance spectrum.The electronic band structure along with density of states(DOS) calculated by DFT method indicates that compound 1 is a semiconductor with an indirect band gap,and that the optical absorption is mainly originated from the charge transitions from Br-4p and As-4p to the Hg-6s states.  相似文献   

7.
采用直接法合成了新型高氮含能配合物[Zn(DAT)6](ClO4)2(DAT=1,5-二氨基四唑),并用元素分析、傅立叶变换红外光谱对其结构进行了表征.利用缓慢蒸发溶剂法培养出其单晶,采用X射线单晶衍射仪测定其晶体结构,结果表明该晶体属于三方晶系,P3空间群,a=b=1.18398(9)nm,c=0.65700(10)nm,γ=120°,V=0.79760(15)nm3,Z=1.在目标配合物的最小不对称单元中有1个Zn2+,6个DAT分子和2个ClO-4.来自6个DAT分子的6个N原子分别与中心Zn2+配位,形成一个六配位、非中心对称的畸变八面体结构.用差示扫描量热分析、热重-微分热重分析结合红外光谱研究了标题化合物的热分解机理以及分解反应动力学参数.测定了标题配合物的感度性能,结果表明标题配合物具有一定的摩擦感度.  相似文献   

8.
The new ternary phase Ba(5)In(4)Bi(5) was synthesized by direct reaction of the corresponding elements at high temperature. It crystallizes in a noncentrosymmetric space group and represents a new structure type (tetragonal, P4nc with a=10.620(2) and c=9.009(2) A, Z=2). The structure is built of interconnected heteroatomic clusters of In(4)Bi(5), square pyramids with In(4)-bases and four exo-bonded bismuth atoms (bond to the In atoms). According to Wade's rule the compound is electron-deficient with one electron per cluster, that is, [In(4)Bi(5)](10-) instead of the expected [In(4)Bi(5)](11-) for a closed-shell species. The clusters are discussed also in light of the known heteroatomic deltahedral clusters with the same composition but different charge, [In(4)Bi(5)](3-). Band structure calculations on the new compound suggest substantial participation of barium in the overall bonding of the structure that "accounts" for the electron shortage  相似文献   

9.
The alloying behavior of antimony atoms into nm-sized indium clusters has been studied in situ by uvvisible absorption spectroscopy. Using a vacuum evaporator installed in the specimen chamber of a spectrophotometer, antimony atoms are vapor-deposited onto nm-sized indium clusters kept at ambient temperature. Spectra from clusters after antimony deposition onto pure indium clusters can be characterized by a doublet structure with an energy separation corresponding to the spin-orbit splitting of the L 3 valence band state of InSb. It has been confirmed that when antimony is vapor-deposited onto indium clusters, rapid dissolution of antimony into indium clusters takes place to form InSb clusters in the absence of any electron irradiation.  相似文献   

10.
Cole ML  Jones C  Kloth M 《Inorganic chemistry》2005,44(14):4909-4911
The first example of a compound containing a mixed-oxidation-state indium sub-halide complex anion, [In5Br8(quinuclidine)4]-, has been accessed by the controlled decomposition of an indium trihydride adduct, [InH3(quinuclidine)], in the presence of LiBr. An intermediate in this reaction, [InH2Br(quinuclidine)2], has been isolated and suggests that its mechanism involves hydride-bromide exchange, reductive dehydrogenation, and disproportionation processes.  相似文献   

11.
本文报告用单晶X-射线衍射法测定[Nd_2O(C-5H_5)_6](C_(12)H_9N_2)_3C1·mC_4H_5O的晶体结构。晶体属于单斜晶系,空间群为P2-1/c,晶胞参数为a=20.982(15),b=11.217(7),c=32.954(32),β=104.17(7)°;Z=4。Nd和C1原子坐标用直接法定出,其他原子坐标以差Fourier方法求得,经过最小二乘法修正,R因子为0.159。在分子中三个茂环皆通过η~5。键与Nd原子配位,两个Nd原子间存在桥氧原子,因而形成(Nd_2O(C_5H_5)_6)~(2-)阴离子,Nd-C键基本上属于离子键。三个邻菲罗啉基团通过氢键与C1原子连接形成大的阳离子[(C_(12)H_9N_2)3-C1]~(2+)。  相似文献   

12.
The Sr3Tl5 phase was prepared by high temperature synthesis techniques through reaction of the high purity elements in the welded Nb tubes.The structure established through X-ray structural analysis shows the compound is a good hypoelectronic trielide example of the Pu3Pd5 structural type in which skeletal electron count is lower than in a traditional Zintl phase(Cmcm,Z = 4;a = 10.604(2) ,b = 8.675(2) ,and c = 10.985(2) ;V = 1010.5(3) 3).The strontium size and the compound’s polarity appear responsible for this thallium phase crystallization in the Pu3Pd5 family type rather than the isoelectronic Sr3In5 version.A first-principle electronic structure calculation(LMTO) demonstrates that the strontium atoms participate substantially in Sr-Tl bonding in the structure.  相似文献   

13.
The title compounds were prepared from the elements by reactions in water-cooled glassy carbon crucibles under an argon atmosphere in a high-frequency furnace. CaPdIn4 crystallizes with the YNiAl4-type structure: Cmcm, a=446.7(3), b=1665(1), c=754.3(5) pm, wR2=0.0465 with 646 F2 values and 24 variables. The structure is built up from a complex three-dimensional [PdIn4] polyanion in which the calcium atoms occupy distorted pentagonal tubes formed by indium and palladium atoms. CaRhIn4 and CaIrIn4 adopt the LaCoAl4-type structure: Pmma, a=867.6(1), b=422.91(8), c=745.2(1) pm, wR2=0.0583 with 468 F2 values and 24 variables for CaRhIn4; a=869.5(1), b=424.11(6), c=746.4(1) pm, wR2= 0.0614 471 F2 values with 24 variables for CaIrIn4. This structure type, too, has a three-dimensional [RhIn4] polyanion which is related to the structure of binary RhIn3. The calcium atoms fill distorted pentagonal prismatic channels formed by indium atoms. Semi-empirical band structure calculations for Ca-RhIn4 and CaPdIn4 reveal strongly bonding In-In, Rh-In and Pd-In interactions but weaker Ca-Rh, Ca-Pd and Ca-In interactions. CaRhIn4 and Ca-PdIn4 are compared with other indium-rich compounds such as YCoIn5 and Y2CoIn8, and with elemental indium. Common structural motifs of the indium-rich compounds are distorted bcc-like indium cubes.  相似文献   

14.
Ge MH  Corbett JD 《Inorganic chemistry》2007,46(17):6864-6870
The ternary phase Eu3Bi(Sn1-xBix)4 ( approximately 0 < x < approximately 0.15) has been synthesized by solid-state methods at high temperature. The crystal structure of the limiting Eu3Bi(Sn3.39Bi0.61(3)) has been determined by single-crystal X-ray analysis to be isopointal with an inverse-Cr5B3-type structure [space group I4/mcm, Z = 4, a = 8.826(1) A, c = 12.564(3) A, and V = 978.6(3) A3]. The structure contains slabs of three-bonded Sn/Bi atoms as puckered eight- and four-membered rings interlinked at all vertices, and these are separated by planar layers of individual Eu and Bi atoms. In the normal (stuffed) Cr5B3-type analogue Eu5Sn3Hx, these two units are replaced by a more highly puckered network of Eu cations around isolated Sn atoms and planar layers of isolated Eu atoms and Sn dimers, respectively. Band structures of limiting models of the phase calculated by TB-LMTO-ASA methods show a metallic character and indicate that the mixed Sn/Bi occupancy in the slabs in this structure for x > 0 probably originates with the electronic advantages of the pseudogap that would occur at the electron count of the ideal Zintl phase Eu3Bi(Sn3Bi). The stability of a competing phase reduces this limit to Eu3Bi(Sn3.4Bi0.6).  相似文献   

15.
You TS  Grin Y  Miller GJ 《Inorganic chemistry》2007,46(21):8801-8811
The ternary polar intermetallic compounds EuGaTt (Tt = Si, Ge, Sn) have been synthesized and characterized experimentally, as well as theoretically. EuGaSi crystallizes in the hexagonal AlB(2)-type structure (space group P6/mmm, Z = 1, Pearson symbol hP3) with randomly distributed Ga and Si atoms on the graphite-type planes: a = 4.1687(6) A, c = 4.5543(9) A. On the other hand, EuGaGe and EuGaSn adopt the hexagonal YPtAs-type structure (space group P6(3)/mmc, Z = 4, Pearson symbol hP12): a = 4.2646(6) A and c = 18.041(5) A for EuGaGe; a = 4.5243(5) A and c = 18.067(3) A for EuGaSn. The three crystal structures contain formally [GaTt](2-) polyanionic 3-bonded, hexagonal networks, which change from planar to puckered and exhibit a significant decrease in interlayer Ga-Ga distances as the size of Tt increases. Magnetic susceptibility measurements of this series of compounds show Curie-Weiss behavior above 86(5), 95(5), and 116(5) K with magnetic moments of 7.93, 7.97, and 7.99 mu(B) for EuGaSi, EuGaGe, and EuGaSn, respectively, indicating a 4f(7) electronic configuration (Eu(2+)) for Eu atoms. X-ray absorption spectra (XAS) are also consistent with these magnetic properties. Electronic structure calculations supplemented by a crystal orbital Hamilton population (COHP) analysis identifies the synergy between atomic sizes, from both Eu and Tt atoms, and the orbital contributions from Eu toward influencing the structural features of EuGaTt. A multicentered interaction between planes of Eu atoms and the [GaTt](2-) layers rather than through-space Ga-Ga bonding is seen in ELF distributions.  相似文献   

16.
A nickel-1,10-phenanthroline complex supported on an octamolybdate, [{Ni(phen)2}2(x- Mo8O26)], has been hydrothermally synthesized with MoO3, H2MoO4, Ni(OAc)2· 6H2O and 1,10-phenathroline (1,10-phen) as raw materials. The crystals of the compound belong to monoclinic P21/n space group, a = 1.2952(2), b = 1.6659(10), c = 1.3956(12) nm, b =106.273(8)°, V = 2.8906(5) nm3, Z = 2. 5604 observable reflections (I >2s(I)) were used for structure resolution and refinements to converge to final R1 = 0.0414, wR2 = 0.0815. The result of structure determination shows that the compound contains octamolybdate possessing a novel structure type (named as x-isomer). The feature of x-[Mo8O26]4- is that it is composed of Mo6O6 ring and two MoO6 octahedra located at cap positions on opposite faces. The Mo6O6 ring contains two octahedral and four trigonal-bipyramidal MoVI atoms. Each x-[Mo8O26]4- unit is bonded with two [Ni(phen)2]2+ through terminal oxygen atoms of octahedral and neighbouring trigonal-bipyramidal Mo atom in the Mo6O6 ring. IR and UV-Vis spectra of the compound were measured and its electronic structure was studied by EHMO method.  相似文献   

17.
具有开放骨架结构的金属酸盐在作为微孔材料、非线性光学材料、催化剂载体和离子交换剂等方面具有应用前景 [1] .自从报道第一个具有微孔结构的磷酸铝 [2 ]以来 ,许多其它具有开放骨架结构的金属磷酸盐被合成出来 ,它们的性质和潜在的应用研究也备受关注 [3~ 8] .本文采用温和条件下的水热法 ,合成得到了具有螺旋链状结构的磷酸铟钠盐 [Na6 In4 [P7O2 4 ( OH) 5]· 4H2 O,并采用 X射线单晶衍射方法进行结构测定 ,其结构中包含了共顶角的多面体连接成的螺旋链 ,链间的连接形成多面体四元环和八元环 ,3个四元环围成了一个三配位氧为中心…  相似文献   

18.
A new nickel(Ⅱ)-dicyanamide compound, [Ni(dca)2(en)]n (1) (dca=dicyanamide anion, [N(CN)2]-); en=ethylene diamine), has been synthesized and its structure has been determined by single crystal X-ray diffraction analysis. The crystal is monoclinic, space group P21/n with unit cell dimensions: a=0.694 3(1) nm, b=1.041 5(2) nm, c=1.4132(2) nm, and β=90.381°, Z=4, V=1.011 0(3) nm3. In this compound, the adjacent nickel atoms are connected by dca all in μ1,5-bridging mode to form ladder-like units, which are linked with double dca bridges to generate a regular infinite stair-like structure. Temperature-dependent magnetic susceptibility was also characterized for this compound. CCDC: 208276.  相似文献   

19.
The synthesis by arc-melting techniques, the single-crystal X-ray structure, and the theoretical analysis of Gd4B3C4 are reported. It crystallizes in the triclinic space group P1 with a = 3.637(2) A, b = 3.674(2) A, c = 11.859(5) A, alpha = 93.34(5) degrees, beta = 96.77(5) degrees, gamma = 90.24(5) degrees, and Z = 1. In this structure, the boron and carbon atoms form two different types of nonmetal arrangements: 1-D (BC)infinity branched chains and finite (0-D) linear CBC "molecular" units. Gd4B3C4 is the first characterized member of the rare earth metal borocarbide series in which both 1-D and "molecular" 0-D nonmetal atom systems coexist. From the structural and theoretical analysis, the following formal charge distribution can be proposed within the ionic limit: (Gd3+)4(BC2(5-)(BC3-)2.e-. Tight-binding calculations suggest that the excess electron in the ionic limit is mainly localized on the Gd atoms (at the bottom of the 5d band), while LAPW calculations favor its localization on the (BC)infinity chain. The bonding within this compound is fully analyzed and compared to other members of the rare earth metal borocarbide series.  相似文献   

20.
Cobalt(II), nickel(II), and copper(II) (1, 2, and 3) complexes of the dianionic form of the bis(phenolate) ligand N,N-bis(3,4-dimethyl-2-hydroxybenzyl)-N',N'-dimethylethylenediamine (H2L) have been synthesized by electrochemical oxidation of the appropriate metal in an acetonitrile solution of the ligand. When copper is used as the anode, the addition of 1,10-phenanthroline to the electrolytic phase gave rise to a different compound [CuL]2.2CH3CN (4). The compounds [CoL]2.2CH3CN (1), [Ni2L2(H2O)].H2O (2), [CuL]2.3H2O (3), and [CuL]2.2CH3CN (4) were characterized by microanalysis, IR, electronic spectroscopy, FAB mass spectrometry, magnetic measurements and by single-crystal X-ray diffraction. The crystal structures show that the complexes have a dinuclear structure. In compounds 1, 3, and 4, two metal ions are coordinated by the two amine nitrogens and the two phenol oxygen atoms of a deprotonated pendant phenol ligand, with one phenolic oxygen atom from ligand acting as a bridge. In compounds 1 and 3, each metal center has a geometry that is closest to trigonal bipyramidal. Magnetic susceptibility data for both compounds show an antiferromagnetic coupling with 2J = -15 cm(-1) for the cobalt(II) complex and a strong antiferromagnetic coupling with 2J = -654 cm(-1) for the copper(II) complex. However, in 4 the geometry around the metal is closer to square pyramidal and the compound shows a lower antiferromagnetic coupling (2J = -90 cm(-1)) than in 3. The nickel atoms in the dimeric compound 2 are hexacoordinate. The NiN2O4 chromophore has a highly distorted octahedral geometry. In this structure, a dianionic ligand binds to one nickel through the two amine nitrogen atoms and the two oxygen atoms and to an adjacent nickel via one of these oxygen atoms. The nickel atoms are linked through a triple oxygen bridge involving two phenolic oxygens, each from a different ligand, and an oxygen atom from a water molecule. The two nickel ions in 2 are ferromagnetically coupled with 2J = 19.8 cm(-1).  相似文献   

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