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1.
The reaction of Rb2S3, Ta and S in a 1.3 : 1 : 5.6 molar ratio at 400 °C yields red‐orange crystals of the new ternary compound Rb6Ta4S22 being the first tantalum polysulfide containing the dimeric complex anion [Ta4S22]6–. The polysulfide anions are composed of two Ta2S11 subunits which are linked to Ta4S22 units via terminal sulfur ligands. The Ta5+ centers are coordinated by S22– and S2– ligands according to [(Ta2(μ2‐η2,η1‐S2)3(η2‐S2)(S)2)2(μ2‐η1,η1‐S2)]6–. Every Ta5+ ion is surrounded by seven sulfur ions forming a strongly distorted pentagonal bipyramid. In the crystal structure the discrete [Ta4S22]6– anions are stacked parallel to the crystallographic b‐axis. The Rb+ cations are located between these stacks. Rb6Ta4S22 crystallizes in the monoclinic space group P21/c (No. 14) with a = 11.8253(9) Å, b = 7.9665(4) Å, c = 19.174(2) Å, β = 104.215(9)°, V = 1751.0(2) Å3, Z = 2. 相似文献
2.
The mixed‐valent oxotantalate Eu1.83Ta15O32 was prepared from a compressed mixture of Ta2O5 and the metals in a sealed Ta ampoule at 1400 °C. The crystal structure was determined by means of single crystal X‐ray diffraction: space group R3¯, a = 777.2(6) pm and c = 3523.5(3) pm, Z = 3, 984 symmetrically independent reflections, 83 variables, RF = 0.027 for I > 2σ (I). The structure is isotypic to Ba2Nb15O32. The salient feature is a [Ta(+8/3)6O12iO6a] cluster consisting of an octahedral Ta6 core bonded to 12 edge‐bridging inner and six outer oxygen atoms. The clusters are arranged to slabs which are sandwiched by layers of [Ta(+5)3O13] triple octahedra. Additional Ta(+5) and Eu(+2) atoms provide the cohesion of these structural units. Twelve‐fold coordinated Eu(+2) atoms are situated on a triply degenerate position 33 pm displaced from the threefold axis of symmetry. A depletion of the Eu(+2) site from 6 to 5.5 atoms per unit cell reduces the number of electrons available for Ta‐Ta bonding from 15 to 14.67 electrons per cluster. Between 125 and 320 K Eu1.83Ta15O32 is semi‐conducting with a band gap of 0.23 eV. The course of the magnetization is consistently described with the Brillouin function in terms of a Mmol/(NAμB) versus B/T plot in the temperature range 5 K — 320 K and at magnetic flux densities 0.1 T — 5 T. At moderate flux densities (< 1 T) the magnetic moment agrees fairly well with the expected value of 7.94 μB for free Eu (2+) ions with 4f7 configuration in 8S7/2 ground state. Below 5 K, anisotropic magnetization measurements at flux densities B < 1 T point to an onset of an antiferromagnetic ordering of Eu spins within the layers and an incipient ferromagnetic ordering perpendicular to the layers. 相似文献
3.
Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl, Br, NO3) cocrystallize in aqueous solutions of [Ta6Br12]2+ in the presence of Cu2+ ions. The crystal structures of [Ta6Br12(H2O)6]Cl2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 1 ) and [Ta6Br12(H2O)6]Br2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta6Br12]2+ in the [Ta6Br12(H2O)6]2+ cation and [Ta6Br12]4+ in trans‐[Ta6Br12(OH)4(H2O)2]. Average bond distances in the [Ta6Br12(H2O)6]2+ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Bri , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Bri , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta6‐Br12(OH)4(H2O)2]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Bri, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H2O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Bri, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H2O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta6Cl12]2+ oxidized to [Ta6Cl12]4+ , whereas [Nb6X12]2+ clusters were not affected by the Cu2+ ion. 相似文献
4.
5.
Using hydrothermal methods, two manganese arsenates have been synthesized and characterized by single crystal X‐ray diffraction. The products Mn5(AsO4)2(HAsO4)2 ?4H2O ( 1 ) and Mn2AsO4(OH) ( 2 ), the Mn end‐members of the minerals villyaellenite and sarkinite, respectively, have been obtained (crystal data 1 : monoclinic, C2/c, a = 18.109(4), b = 9.332(2), c = 9.809(2) Å, β = 96.172(4)?, Z = 4; 2 : monoclinic, P21/c, a = 10.219(2), b = 13.613(2), c = 12.780(2) Å, β = 108.834(2)?, Z = 16). In both compounds a three‐dimensional framework of edge‐sharing MnO polyhedra is observed. Based on the availability of the all Mn2containing form of villyaellenite ( 1 ), the ordering scheme of the impurity cations of the natural samples could be confirmed. Magnetic susceptibility measurements of 1 indicate the presence of high‐spin Mn2+ ions. The comparison of the data on sarkinite ( 2 ) with the data obtained from the natural sample indicates that the mineral has either a very high Mn content, or an absence of impurity cation ordering. 相似文献
6.
Preparative exploration of the system Ag—Mn—O under an elevated oxygen pressure yielded so far unknown Ag4Mn3O8. Single crystal X‐ray investigations have revealed a trigonal crystal system, space group P3121 with lattice parameters a = 12.5919(1) and c = 15.4978(1)Å. Due to fourfold twinning a large cubic unit cell with a ≈ 26Å is simulated. The structure, which was refined as a fourfold twin, is composed of MnO6 octahedra which are connected via common edges to a complex framework. The topology of this framework is closely related to the archetype cubic {10, 3} net. In the cavities of the framework the Ag+ ions are incorporated. 相似文献
7.
Reaction of Mn(NCS)2 with 4-picoline (4-methylpyridine) leads to the formation of [Mn(NCS)2(4-picoline)4] · 0.67 · 4-picoline · 0.33 · H2O ( 1 - Mn ) reported in literature, Mn(NCS)2(4-picoline)2(H2O)2 ( 2-Mn/H2O ), and of [Mn(NCS)2(4-picoline)2]n ( 2-Mn/I ). 1-Mn and 2-Mn/H2O consist of discrete complexes, in which the metal cations are octahedrally coordinated, whereas in 2-Mn/I the metal cations are linked by pairs of μ-1,3-bridging thiocyanate anions into corrugated chains. Measurements using thermogravimetry and differential scanning calorimetry as well as temperature dependent X-ray powder diffraction on 1-Mn and 2-Mn/H2O reveal that upon heating both compounds transform into [Mn(NCS)2(4-picoline)]n ( 3-Mn ) via 2-Mn/I as intermediate. 3-Mn shows a very rare chain topology in which the metal cations are linked by μ-1,3,3 (N,S,S) coordinating anionic ligands which was never observed before with MnII. From these investigations there is no hint that a further modification of 2-Mn can be prepared as recently observed for [M(NCS)2(4-picoline)2]n (M = Fe, Cd) and such a form is also not available if the metastable forms of the FeII or CdII compounds were used as template during thermal decomposition. Magnetic investigations on 2-Mn/H2O show only paramagnetic behavior, whereas for 2-Mn/I antiferromagnetic ordering is observed. Finally, the crystal structure of Mn(NCS)2 was determined from XRPD data, which shows that it is strongly related to that of 3-Mn . 相似文献
8.
Lei Meng Jing Li Zhen‐Gang Sun Xue‐fang Zheng Da‐Peng Dong Hui Chen Yan‐Yu Zhu Yan Zhao Jing Zhang 《无机化学与普通化学杂志》2008,634(3):571-574
Two manganese phosphonates Mn2[{(O3PCH2)2NHR}(H2O)F]·H2O (R = ?C6H11 (1) , ?CH2C5H4N (2) ) have been synthesized by hydrothermal reaction and characterized by single–crystal X–ray diffraction as well as with infrared spectroscopy, elemental analysis and thermogravimetric analysis. The two isomorphous compounds feature layered structures in ab plane, in which the tetramers comprised of two MnO4F2 and two MnO5F polyhedra are cross–linked via phosphonate oxygen atoms to form MnII phosphonate layers. The organic groups of the ligands are orientated toward the interlayer space. 相似文献
9.
在碱金属离子或碱土金属离子与过渡金属离子共存的情况下,全氧冠醚一般选择前者与之配位[1,2],而与过渡金属离子直接配位的情况则报道较少[3,4]我们在Na+与Mn2+共存的体系中制得了标题配合物的单晶体,并用四圆衍射仪测定了其晶体结构和分子结构.本文对进一步探讨全氧冠醚与过渡金属离子的配位性能及配位特点具有重要的意义.1实验部分1.1单晶生长在10mL称量瓶中,加入0.5gMnCI。·4H。0、08gNaSCN和5mL蒸馏水,溶解后再加入0.ig15一冠一5,搅拌均匀,静置于有机玻璃恒温箱中(25士0.SC),6h后长出无色棒状单晶.经红外… 相似文献
10.
The structure of completely exchanged Mn2+—ß″—Al2O3(Mn0.77Al10.46Mg0.54O17) crystals has been investigated by single—crystal X—ray diffraction methods at room temperature (trigonal, R3¯, Z = 3, a = 560.65(7), c = 3329.3(9) pm). The manganese ions (Mn2+) are found to occupy Beevers‐Ross (56 %) and mid—oxygen positions (44 %) in nearly the same amounts. The crystal composition was confirmed by electron probe microanalyses on various crystals. 相似文献
11.
The new ternary compound Tl4Ta2Se11 was prepared in a melt of thallium polyselenides applying elemental tantalum. It crystallises in the triclinic space group P1¯ with a = 7.996(1) Å, b = 9.866(1) Å, c = 13.668(2) Å, α = 73.03(1)°, β = 89.21(2)° and γ = 85.72(1)°. Tl4Ta2Se11 is the first polyselenide with discrete complex [M2Se11]4— anions. Every Ta atom is in a sevenfold environment of Se atoms to form a distorted pentagonal bi‐pyramid. The two TaSe7 polyhedra have a face in common thus yielding the [Ta2Se11]4— unit. In the structure, the anions are well separated by the Tl1+ cations. An assignment of the different vibration modes in the IR and Raman spectra is given based on density functional calculations. 相似文献
12.
The new compounds K6Nb4S22 and K6Ta4S22 ( I ) have been synthesised by the reaction of NbS2 or Ta metal in a K2S3 flux. Using TaS2 as educt a second modification of K6Ta4S22 ( II ) is obtained. K6Nb4S22 and K6Ta4S22 (form I ) crystallise in the monoclinic space group C2/c with a = 35.634 (2)Å, b = 7.8448 (4)Å, c = 12.1505 (5)Å, β = 100.853 (5)°, V = 3335.8 (3)Å3, and Z = 4 for K6Nb4S22 and a = 35.563 (7) Å, b = 7.836 (2)Å, c = 12.139 (2)Å, β = 100.56 (3)°, V = 3325.5 (2)Å3, and Z = 4 for K6Ta4S22 ( I ). The second modification K6Ta4S22 (form II ) crystallises in the monoclinic space group P21/c with a = 7.5835 (6)Å, b = 8.7115 (5)Å, c = 24.421 (2)Å, β = 98.733 (9)°, V = 1594.6 (2)Å3, and Z = 2. The structures consist of [M4S22]6— anions composed of two M2S11 sub‐units which are linked into M4S22 units via terminal sulfur ligands. The anions are well separated by the K+ cations. Differences between the structures of the title compounds and those with the heavier alkali cations Rb+ and Cs+ are caused by the different arrangement of the [M4S22]6— anions around the cations and the different S2—/S22— binding modes. The thermal behaviour of both modifications was investigated using differential scanning calorimetry (DSC). From these investigations there is no hint for a polymorphic transition between the two forms. After heating crystals of form II above the melting point and cooling the melt to room temperature a crystalline powder of form I can be isolated. 相似文献
13.
TlTaS3 was prepared by applying a sequence of two melting processes with mixtures of Tl2S, Ta, and S having different molar metal to sulphur ratios. TlTaS3 crystallises in space group Pnma with a = 9.228(3)Å, b = 3.5030(6)Å, c = 14.209(3)Å, V = 459.3(2)Å3, Z = 4. The structure is closely related to the NH4CdCl3‐type. Characteristic features of the structure are chains of edge‐sharing [Ta(+5)S4S2/2]2 double octahedra running along [010]. These columns are linked by Tl+ ions. The Tl+ ion is surrounded by eight S2— anions to form a distorted bi‐capped trigonal prism. The Tl+ ions are shifted from the centre of the trigonal prism toward one of the rectangular faces. This is discussed in context with other isostructural compounds. TlTaS3 is a semiconductor. The electronic structure is discussed on the base of band structure calculations performed within the framework of density functional theory. 相似文献
14.
Weifeng Shi Le Zhang Maryam Shafaei‐Fallah Alexander Rothenberger Dr. 《无机化学与普通化学杂志》2007,633(3):440-442
The synthesis and structures of three new compounds are reported. [Mg2{PhP(Se,O)Se‐Se(O,Se)PPh}2(thf)7(H2O)3] ( 1 ), [Mg{PhP(Se,O)Se‐Se(O,Se)PPh}(thf)3(H2O)] ( 2 ), and [Mn{PhP(Se,O)Se‐Se(O,Se)PPh}(thf)3(H2O)] ( 3 ) were prepared by treatment of Woollins' reagent [PhP(Se)(μ‐Se)]2 with the corresponding hydrated metal acetates. 相似文献
15.
《Journal of Coordination Chemistry》2012,65(1):59-64
The complex (benzoato)benzoylacetonato(bipyridine)Mn(II) has been prepared and its crystal structure determined by X-ray diffraction methods. Benzoic acid, benzoylacetone (bzac) and 2,2'-bipyridine all chelate to Mn(II) to form a six coordinate complex. As bond angles around the Mn(II) atom greatly deviate from those expected for an octahedron, the coordination geometry may be described as distorted pyramidal with a bidentate carboxyl group occupying the apex of the pyramid. Although the Mn atom deviates by 0.550 Å from the enol ring plane of bzac, Mn-O distances [2.105(2) and 2.098(2) Å] are normal. This suggests the existence of electrostatic interactions between Mn(II) and the bzac ligand. 相似文献
16.
Contributions on the Bonding Behaviour of Oxygen in Inorganic Solids. III [1] Mn2P2O7, Mn2P4O12 und Mn2Si(P2O7)2 — Crystal Growth, Structure Refinements and Electronic Spectra of Manganese(II) Phosphates By chemical vapour transport reactions in a temperature gradient single crystals of Mn2P2O7 (1050 → 950 °C) and Mn2P4O12 (850 → 750 °C) have been obtained using P/I mixtures as transport agent. Mn2Si(P2O7)2 was crystallized by isothermal heating (850 °C, 8d; NH4Cl as mineralizer) of Mn2P4O12 und SiO2. In Mn2Si(P2O7)2 [C 2/c, a = 17.072(1)Å, b = 5.0450(4)Å, c = 12.3880(9)Å, β = 103.55(9)°, 1052 independent reflections, 97 variables, R1 = 0.023, wR2 = 0.061] the Mn2+ ions show compressed octahedral coordination (d¯Mn—O = 2.19Å). The mean distance d¯Mn—O = 2.18Å was found for the radially distorted octahedra [MnO6] in Mn2P4O12 [C 2/c, Z = 4, a = 12.065(1)Å, b = 8.468(1)Å, c = 10.170(1)Å, β = 119.29(1)°, 2811 independent reflections, 85 variables, R1 = 0.025, wR2 = 0.072]. Powder reflectance spectra of the three pink coloured manganese(II) phosphates have been measured. The spectra show clearly the influence of the low‐symmetry ligand fields around Mn2+. Observed d—d electronic transition energies and the results of calculations within the framework of the angular overlap model (AOM) are in good agreement. Bonding parameters for the manganese‐oxygen interaction in [Mn2+O6] chromophors as obtained from the AOM treatment (B, C, Trees correction α, eσ, eπ) are discussed. 相似文献
17.
《Journal of Coordination Chemistry》2012,65(20):2257-2263
The reaction of the decadentate ligand tpmen (H4tpmen?=?N,N,N′N′-tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine) with MnCl2·4H2O in aqueous solution gives a homodinuclear complex [Mn2(H2O)2(tpmen)]·16H2O, which has been characterized by elemental analysis, thermal gravimetric and single-crystal X-ray diffraction analysis. The complex crystallizes in the orthorhombic system, space group Cmca, a?=?28.786(5) Å, b?=?11.5033(19) Å, c?=?14.437(2) Å, Z?=?8, R 1?=?0.0432, wR 2?=?0.0786. The tpmen ligand contains four picolinate groups, two of which bind each Mn(II) to form a dinuclear complex. The geometry around the Mn(II) is distorted octahedral with two nitrogen and two oxygen atoms from the picolinate groups and two oxygen atoms from coordinated water. The variable-temperature (2–300?K) magnetic susceptibilities shows an antiferromagnetic interaction between Mn(II) ions. 相似文献
18.
The crystal structure of lead cyanamide, PbNCN, has been refined on the basis of a single crystal grown from solution. PbNCN crystallizes in space group Pnma (Z = 4) with a = 555.66(4) pm, b = 386.77(2) pm, and c = 1173.50(8) pm. The cyanamide anion exhibits C–N bond lengths of 116 pm and 130 pm, and the N–C–N angle is 176°. Quantum‐chemical DFT calculations indicate that the cyanamide unit is comparatively easy to distort. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(9):1518-1524
A manganese(II) coordination polymer [Mn(TMB)2?·?H2O] n (1) (HTMB?=?3,4,5-trimethoxybenzoic acid) has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, powder X-ray diffraction analysis, spectroscopic (IR, solid state UV-Vis), and thermal methods. The crystal belongs to orthorhombic system, space group P212121, with cell parameters a?=?7.3001(8), b?=?11.4146(13), c?=?27.053(3)?Å, α?=?β?=?γ?=?90°, V?=?2254.3(4)?Å3, Z?=?4. In 1, TMB in two different coordination modes bridges six-coordinate manganese(II) centers forming a 1-D infinite chain coordination framework. The spectral and thermal properties of the complexes have also been studied. 相似文献
20.
Wan‐Feng Lin Qiu‐Ju Xing Jun Ma Jian‐Ping Zou Si‐Liang Lei Xu‐Biao Luo Guo‐Cong Guo 《无机化学与普通化学杂志》2013,639(1):31-34
The new spiroffite Mg2Te3O8 ( 1 ) was prepared by hydrothemal methods and structurally characterized by single‐crystal X‐ray diffraction analysis. Compound 1 crystallizes in the space group C2/c of the monoclinic system with two formula units in a cell: a = 12.6030(7), b = 5.2254(3), c = 11.6331(7) Å, β = 98.6960(10)°, V = 757.30(8) Å3. The structure features a 3D open‐framework with spiroffite topology that has large tunnels approximately 3.2 × 5.5 Å. The optical properties and thermal stability of 1 were characterized by UV and IR spectroscopy as well as TG. Calculations of the electronic band structure along with the density of states (DOS) indicate that the present compound is a semiconductor with an indirect band gap, and that the optical absorption is mainly originated from the charge transitions from O‐2p state to Te‐5p and Te‐5s states. 相似文献