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On Hexafluoroindates(II1): A2TlInF6 (A = Rb, Cs), (RbTI)BInF6 (B = Na, Ag, K), and A2AgInF6 (A = Rb, TI, Cs) By heating the binary components in a closed system are new prepared the compounds Rb2AgInF6, Rb2CsInF6, (RbTl)NaInF6 (RbTI)AgInF6, (RbTI)KInF6, Tl2AgInF6, Cs2AgInF6 and Cs2TlInF6, all cubic, colourless Elpasolithes, as well as Rb2TlInF6, according to powder photographs tetragonal. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed. 相似文献
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Mercouri G. Kanatzidis 《无机化学与普通化学杂志》2016,642(19):1120-1125
The new compounds A2ZnP2Se6 (A = K, Rb, Cs) were synthesized via molten salt flux syntheses. The crystals feature one‐dimensional 1/∞[ZnP2Se6]2– chains charge balanced by alkali metal ions between the chains. K2ZnP2Se6 crystallizes in the monoclinic space group P21/c; cell parameters a = 12.537(3) Å, b = 7.2742(14) Å, c = 14.164(3) Å, β = 109.63(3)°, Z = 4, and V = 1216.7(4) Å3. Rb2ZnP2Se6 and Cs2ZnP2Se6 are isotypic, crystallizing in the triclinic space group P$\bar{1}$ . Rb2ZnP2Se6 has cell parameters of a = 7.4944(15) Å, b = 7.6013(15) Å, c = 12.729(3) Å, α = 96.57(3)°, β = 105.52(3)°, γ = 110.54(3)°, Z = 2, and V = 636.6(2) Å3. Cs2ZnP2Se6 has cell parameters of a = 7.6543(6) Å, b = 7.7006(6) Å, c = 12.7373(11) Å, α = 97.007(7)°, β = 104.335(7)°, γ = 109.241(6)°, Z = 2, and V = 669.54(10) Å3. 相似文献
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High level ab initio calculations are performed on the ground electronic state of diatomic molecules MgAlk (Alk = Li, Na, K, Rb, Cs). Potential energy curves and dipole moment functions are determined making use of the single-reference unrestricted and restricted coupled-cluster methods with large basis sets. Basic spectroscopic properties of the ground electronic states are derived from ro-vibrational bound state calculations. 相似文献
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Single crystals of A2ThP3Se9 (A = K (I), Rb (II)) and Cs4Th2PsSe17 (III) form from the reaction of Th and P in a molten A2Se3/Se (A = K, Rb, Cs) flux at 750 degrees C for 100 h. Compound I crystallizes in the triclinic space group P1 (No. 2) with unit cell parameters a = 10.4582(5) A, b = 16.5384(8) A, c = 10.2245(5) A, alpha = 107.637(1); beta = 91.652(1); gamma = 90.343(1) degrees, and Z = 2. Compound II crystallizes in the triclinic space group P1 (No. 2) with the unit cell parameters a = 10.5369(5) A, b = 16.6914(8) A, c = 10.2864(5) A, alpha = 107.614(1) degrees, beta = 92.059(1) degrees, gamma = 90.409(1) degrees, and Z = 2. These structures consist of infinite chains of corner-sharing [Th2Se14] units linked by (P2Se6)4- anions in two directions to form a ribbonlike structure along the [100] direction. Compounds I and II are isostructural with the previously reported K2UP3Se9. Compound III crystallizes in the monoclinic space group P2(1)/c (No. 14) with unit cell parameters a = 10.238(1) A, b = 32.182(2) A, c = 10.749(1) A; beta = 95.832(1) degrees, and Z = 4. Cs4Th2P5Se17 consists of infinite chains of corner-sharing, polyhedral [Th2Se13] units that are also linked by (P2Se6)4- anions in the [100] and [010] directions to form a layered structure. The structure of III features an (Se2)2- anion that is bound eta 2 to Th(2) and eta 1 to Th(1). This anion influences the coordination sphere of the 9-coordinate Th(2) atom such that it is best described as bicapped trigonal prismatic where the eta 2-bound anion occupies one coordination site. The composition of III may be formulated as Cs4Th2(P2Se6)5/2(Se2) due to the presence of the (Se2)2- unit. Raman spectra for these compounds and their interpretation are reported. 相似文献
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T. F. Antokhina T. A. Kaidalova N. N. Savchenko L. N. Ignat’eva 《Russian Journal of Coordination Chemistry》2013,39(4):312-315
Ammonium-containing zirconium fluoride complexes of the formula (NH4)6MZr4F23 (M = K, Rb, and Cs) were obtained and studied. The complexes crystallize in the orthorhombic system. Their unit cell parameters were determined. The IR absorption spectra of the complexes in the 350–4000 cm?1 range were recorded and examined. 相似文献
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Miao Yan Hai-Ru Li Xin-Xin Tian Yue-Wen Mu Hai-Gang Lu Si-Dian Li 《Journal of computational chemistry》2019,40(11):1227-1232
Detailed molecular orbital and bonding analyses reveal the existence of both fluxional σ- and π-bonds in the global minima Cs ( 1 ) and Cs MB18 ( 3 ) and transition states Cs ( 2 ) and Cs ( 4 ) of dianion and monoanions (M = K, Rb, and Cs). It is the fluxional bonds that facilitate the fluxional behaviors of the quasi-planar and half-sandwich which possess energy barriers smaller than the difference of the corresponding zero-point corrections. © 2019 Wiley Periodicals, Inc. 相似文献
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John B. Wiley Shiou-Mei Huang Shinho Cho Franois Diederich Robert L. Whetten Kroly Holczer Richard B. Kaner 《Macromolecular Symposia》1992,59(1):389-397
Shielding diamagnetism and X-ray powder diffraction were used to characterize alkali-metal fullerides of sodium, potassium, rubidium, and cesium. The superconducting phase in both the potassium and rubidium systems has the composition A3C60 and a face centered cubic structure with alkali metal filling all octahedral and tetrahedral sites of close packed C60, layers. High pressure magnetic susceptibility measurements on K3C60 showed a negative pressure dependence on the superconducting transition temperature of −0.78 K/kbar. No evidence for superconductivity was observed in either the sodium or cesium systems, even though Na3C60 appears isostructural with K3C60 and Rb3C60. 相似文献
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碱金属硒化物MHgSbSe~3(M=K,Rb, Cs)的晶体结构及其半导体性 质的研究 总被引:2,自引:0,他引:2
用有机溶剂热生长技术(SolvothermalTechnique)制备碱金属硒化物MHgSbSe~3(M=K,Rb,Cs),用单晶X射线衍射技术对其进行晶体结构分析,热分析结果表明,在常温(<200℃)下均为稳定的化合物。光学性质测试表明它们是半导体材料,KHgSbSe~3,RbHgSbSe~3,CsHgSbSe~3的禁带宽度依次为1.85eV,1.75eV,1.65eV。 相似文献
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T. F. Antokhina T. A. Kaidalova N. N. Savchenko L. N. Ignat’eva 《Russian Journal of Inorganic Chemistry》2012,57(12):1535-1539
Ammonium-containing hafnium fluoro complexes (NH4)6MHf4F23 (M = K, Rb, Cs), which crystallize in orthorhombic symmetry, were synthesized and studied. Their unit cell parameters were determined. The IR absorption spectra of the synthesized complexes were studied in the region of 350?C4000 cm?1. 相似文献
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Malliakas CD Yao J Wells DM Jin GB Skanthakumar S Choi ES Balasubramanian M Soderholm L Ellis DE Kanatzidis MG Ibers JA 《Inorganic chemistry》2012,51(11):6153-6163
Black single crystals of A(6)Cu(12)U(2)S(15) (A = K, Rb, Cs) have been synthesized by the reactive flux method. These isostructural compounds crystallize in the cubic space group Ia ?3d at room temperature. The structure comprises a three-dimensional framework built from US(6) octahedra and CuS(3) trigonal planar units with A cations residing in the cavities. There are no S-S bonds in the structure. To elucidate the oxidation state of U in these compounds, various physical property measurements and characterization methods were carried out. Temperature-dependent electrical resistivity measurement on a single crystal of K(6)Cu(12)U(2)S(15) showed it to be a semiconductor. These three A(6)Cu(12)U(2)S(15) (A = K, Rb, Cs) compounds all exhibit small effective magnetic moments, < 0.58 μ(B)/U and band gaps of about 0.55(2) eV in their optical absorption spectra. From X-ray absorption near edge spectroscopy (XANES), the absorption edge of A(6)Cu(12)U(2)S(15) is very close to that of UO(3). Electronic band structure calculations at the density functional theory (DFT) level indicate a strong degree of covalency between U and S atoms, but theory was not conclusive about the formal oxidation state of U. All experimental data suggest that the A(6)Cu(12)U(2)S(15) family is best described as an intermediate U(5+)/U(6+) sulfide system of (A(+))(6)(Cu(+))(12)(U(5+))(2)(S(2-))(13)(S(-))(2) and (A(+))(6)(Cu(+))(12)(U(6+))(2)(S(2-))(15). 相似文献
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By reacting platinum with alkali metals (A = K, Rb, Cs) a new family of binary alkali metal platinides has been synthesized and characterized by chemical analysis, X‐ray powder diffraction, thermal analysis (DTA and DSC), and magnetic measurements. All three compounds exhibit similar XRD‐patterns with strong reflections that can be indexed on the basis of a rhombohedral crystal system (KxPt: a = 2.6462(1), c = 17.123(1); RbxPt: a = 2.6415(1) Å, c = 17.871(1) Å; CsxPt: a = 2.6505(1) Å, c = 18.536(1) Å; x < ½. The a lattice constant is independent on the alkali metal used and of value close to the Pt–Pt distance in NaPt2 (2.645Å). The c parameter increases monotonically with the growing atomic radius of the alkali metal. The average structure of the alloys consists of cubic close packed layers of platinum atoms with layers of disordered alkali metals in between. For all compounds besides the strong reflections small satellites are observed which cannot be indexed together with the rhombohedral peaks in any rational 3‐dimensional lattice. However, these satellites can be indexed as incommensurate modulations within the ab plane (found propagation vectors k = (0.1011, 0.2506, 0) for CsxPt, and k = (0.0168, 0.2785, 0) for RbxPt). 相似文献
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The electronic absorption spectra at 77 K of KFeS2, RbFeS2 and CsFeS2 were measured and the experimental bands were assigned on the basis of ligand-field theory regarding d5 high spin Fe3+ under a field of Td symmetry yielding Δ ≈ ?4500 to ?5000 cm?1. 相似文献
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Two new ternary uranium selenides, AU(2)Se(6) (A = K, Cs), were prepared using the reactive flux method. Single crystal X-ray diffraction was performed on single crystals. The compounds crystallize in the orthorhombic Immm space group, Z = 2. CsU(2)Se(6) has cell parameters of a = 4.046(2) A, b = 5.559(3) A, and c = 24.237(12) A. KU(2)Se(6) has cell parameters of a = 4.058(3) A, b = 5.556(4) A, and c = 21.710(17) A. The compounds are isostructural to the previously reported KTh(2)Se(6). The two-dimensional layered structure is related to ZrSe(3) with the alkali metals residing in the interlayer space. The oxidation states of uranium and selenium were evaluated using X-ray photoelectron spectroscopy (XPS). Uranium was found to be tetravalent, while selenium was found to be in two oxidation states, one of which is -2. The other oxidation state is similar to that found in a polyselenide network. While this structure is known, our work examines how the structure changes through the transactinide series. 相似文献
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The five title compounds were prepared by direct reactions of the corresponding elements at high temperature. Their structures contain isolated anions of tetrahedral NbAs(4) where one of the edges of the tetrahedron is bridged by a third atom. The bridging atom is arsenic in A(6)NbAs(5) (monoclinic, P2(1)/c, Z = 8; with a = 25.774(3) A, b = 9.335(1) A, c = 13.012(1) A, beta = 101.05(1) degrees for A = K; a = 27.629(1) A, b = 9.925(1) A, c = 14.111(1) A, beta = 101.63(1) degrees for A = Rb; and a = 27.405(1) A, b = 9.9447(6) A, c = 13.9964(8) A, beta = 101.210(1) degrees for A = Cs), thallium in K(6)NbTlAs(4) (orthorhombic, Pnma, Z = 4, a = 18.786(1) A, b = 10.4442(4) A, c = 7.715(1) A), and lead in K(8)NbPbAs(5) (monoclinic, C2/c, Z = 8, a = 31.597(9) A, b = 9.353(1) A, c = 13.427(2) A, beta = 95.25(1) degrees ). The lead atom in the latter is bonded to a third arsenic atom as well. Magnetic measurements showed diamagnetic behavior, and therefore, the compounds are electronically balanced, closed-shell type compounds and can be described as transition-metal Zintl phases. The bonding in the anion NbAs(5)(6-) is discussed in detail. 相似文献
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The title compounds, which are synthesized from be elements, are shown to be isostructural with K8In11 (R3¯c Z=6) and to contain pentacapped trigonal prismatic clusters that have been compressed along the three-fold axes so as to bring the two types of capping atoms within bonding distances. These are arranged in double-ccp layers separated by double alkali--metal layers. Extended Hückel calculations show a substantial energy gap and the end of significant intracluster bonding for the hypoelectronic (by Wade's rules) 18-electron Tl11 7?. Correspondingly, all three compounds are metallic (ρ298 ≈ 400 μΩ · cm) and Pauli-paramagnetic (χM ≈ 4 x 10?4 emu. mol?1, consistent with their formulation as metallic (A +)8Tl11 7? e? phases. Factors thought to be responsible for the cluster distortion, the metallic salt characteristics, and the unusual chemistry of thallium am noted. 相似文献
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On the Tetrabromothallates MTlBr4 (M = K, Rb, Cs, NH4) The tetrabromothallates MTlBr4 (M = K, Rb, Cs, NH4) were obtained by dehydratisation of the appropriate hydrates MTlBr4 · nH2O and by the reaction of TlBr, MBr, and Br2 in closed glass tubes at 400°C. KTlBr4 and NH4TlBr4 crystallize orthorhombic in the Ga[GaCl4]-type with the following lattice constants a = 795.2(3), b = 1036.0(4), c = 1042.1(5) pm (KTlBr4), and a = 812.6(3), b = 1070.1(13), c = 1110.6(10) pm (NH4TlBr4), respectively. 相似文献
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On Hexafluoroferrates(III): Cs2TlFeF6, Cs2KFeF6, Rb2KFeF6, Rb2NaFeF6, and Cs2NaFeF6 New prepared are the compounds Cs2TlFeF6 (a = 9.211 Å), Cs2KFeF6 (a = 9.041 Å), Rb2KFeF6 (a = 8.868 Å) and Rb2NaFeF6 (a = 8.46 4Å) all cubic Elpasolithes as well as Cs2NaFeF6 (Cs2NaCrF6?type, hexagonal with a = 6.281, c = 30.532 Å), all colourless. Cs2KFeF6 was measured magnetically (70–297,2 K). The spectra of reflection were measured (9000–36000 cm?1). The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed. 相似文献
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B. P. Burylev E. B. Kritskaya V. E. Kritskii 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(12):1883-1886
Our own experimental studies of vapor pressure and surface tension were used to analyze isotherms of various types of the properties under consideration. The data obtained were processed using a mathematical model to calculate the molar surface and excess molar Gibbs energy, which clearly indicated that the surface properties obeyed the general rules that governed changes in these properties of solutions according to the position of alkali metals in the periodic table of the elements. The data on various physicochemical properties of the cesium chloride-manganese chloride system are evidence of the presence of singular extremum points on concentration dependence isotherms. 相似文献