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71.
72.
Bi53+ Polycations in Ordered and Plastic Crystals of Bi5[AlI4]3 and Bi5[AlBr4]3 Dark‐red air‐sensitive crystals of pentabismuth‐tris(tetrabromoaluminate) Bi5[AlBr4]3 and black crystals of Bi5[AlI4]3 have been crystallized from melts of Bi, BiX3 and AlX3 (X = Br, I). X‐ray diffraction on a single crystal of Bi5[AlI4]3 (T = 293(2) K; space group Pnma; a = 2143.6(3) pm, b = 1889.1(1) pm, c = 811.74(5) pm) revealed an ordered packing of Bi53+ trigonal bipyramids and [AlI4]? tetrahedra that corresponds to the PuBr3 structure type. Contrary to the so far known Bi53+ polycations with accurate D3h symmetry, the bismuth cluster found in Bi5[AlI4]3 holds only Cs symmetry. The room temperature structure of the tetrabromoaluminate Bi5[AlBr4]3, which is related to the AuCu3 type, shows a dynamic disorder of the Bi53+ polycations (T = 293(2) K; space group ; a = 1766.2(3) pm). Slight cooling induces the transition into an ordered rhombohedral phase isostructural to Bi5[AlCl4]3 (T = 260(2) K; space group a = 1241.5(8) pm, c = 3041(2) pm). 相似文献
73.
Dr. Kai‐Oliver Feldmann Dr. Thomas Wiegand Dr. Jinjun Ren Prof. Dr. Hellmut Eckert Joachim Breternitz Matthias F. Groh Ulrike Müller Prof. Dr. Michael Ruck Dr. Boris Maryasin Prof. Dr. Christian Ochsenfeld Dr. Oliver Schön Prof. Dr. Konstantin Karaghiosoff Prof. Dr. Jan J. Weigand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9697-9712
Although a fairly large number of binary group 15/16 element cations have been reported, no example involving phosphorus in combination with a group 16 element has been synthesized and characterized to date. In this contribution is reported the synthesis and structural characterization of the first example of such a cation, namely a nortricyclane‐type [P3Se4]+. This cation has been independently discovered by three groups through three different synthetic routes, as described herein. The molecular and electronic structure of the [P3Se4]+ cage and its crystal properties in the solid state have been characterized comprehensively by using X‐ray diffraction, Raman, and nuclear magnetic resonance spectroscopies, as well as quantum chemical calculations. 相似文献
74.
Bridging Nonaselenium Ring in [Se9(IrBr3)2], and Three Modifications of the Mononuclear Complex [IrBr3(SeBr2)3]
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The reaction of iridium powder with an excess of selenium and SeBr4 yielded lustrous, vermillion crystals of the mononuclear iridium complex [IrBr3(SeBr2)3]. The transition metal is coordinated octahedrally by three SeBr2 and three bromide ligands with facial or meridional configuration. Three different modifications were obtained under similar conditions: a‐fac‐IrBr3(SeBr2)3, space group P$\bar{1}$ , with a = 789.4(1) pm, b = 830.4(1) pm, c = 1334.4(1) pm, α = 81.634(5)°, β = 84.948(5)°, γ = 67.616(4)°; m‐fac‐IrBr3(SeBr2)3, space group P21/n, with a = 1205.3(1) pm, b = 962.4(1) pm, c = 1383.9(1) pm, β = 91.114(3)°; mer‐IrBr3(SeBr2)3, space group P21/n with a = 859.7(1) pm, b = 1284.3(1) pm, c = 1437.5(1) pm, β = 94.427(3)°. A lower bromine content in the starting composition resulted in shiny, deep‐red crystals of [Se9(IrBr3)2]. X‐ray diffraction on a single‐crystal revealed a tetragonal lattice (space group I41/a) with a = 1245.4(1) pm and c = 2486.8(1) pm at 296(1) K. In the [Se9(IrBr3)2] complex, a crown‐shaped uncharged Se9 ring coordinates two iridium(III) cations as a bridging bis‐tridentate ligand. Three terminal bromide ions complete the distorted octahedral coordination of each transition metal atom. 相似文献
75.
Mai Lê Anh Dr. Martin Kaiser Dr. Madhav Prasad Ghimire Dr. Manuel Richter Dr. Klaus Koepernik Markus Gruschwitz Prof. Dr. Christoph Tegenkamp Prof. Dr. Thomas Doert Prof. Dr. Michael Ruck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15549-15557
Topological insulators (TIs) gained high interest due to their protected electronic surface states that allow dissipation-free electron and information transport. In consequence, TIs are recommended as materials for spintronics and quantum computing. Yet, the number of well-characterized TIs is rather limited. To contribute to this field of research, we focused on new bismuth-based subiodides and recently succeeded in synthesizing a new compound Bi12Rh3Sn3I9, which is structurally closely related to Bi14Rh3I9 – a stable, layered material. In fact, Bi14Rh3I9 is the first experimentally supported weak 3D TI. Both structures are composed of well-defined intermetallic layers of ∞2[(Bi4Rh)3I]2+ with topologically protected electronic edge-states. The fundamental difference between Bi14Rh3I9 and Bi12Rh3Sn3I9 lies in the composition and the arrangement of the anionic spacer. While the intermetallic 2D TI layers in Bi14Rh3I9 are isolated by ∞1[Bi2I8]2− chains, the isoelectronic substitution of bismuth(III) with tin(II) leads to ∞2[Sn3I8]2− layers as anionic spacers. First transport experiments support the 2D character of this material class and revealed metallic conductivity. 相似文献
76.
Melting reactions of Bi2S3, CuX (X = Cl, Br), copper, and sulfur resulted in black needles of qua‐ and quinternary copper bismuth sulfide halogenides. Cu3BiS2Br2 (I) has a melting point of 638(5) K and crystallizes in the orthorhombic space group Pnma with a = 804.50(6) pm, b = 393.27(3) pm, and c = 2253.2(2) pm at T = 293(2) K. Cu4Bi3S5Br3–xClx (x = 1.19(2)) (II) crystallizes in the monoclinic space group I2/m with lattice parameters a = 1573.7(2) pm, b = 397.52(3) pm, c = 2164.9(3) pm, and β = 95.66(1) °. Both compounds exhibit networks of thio‐halogenido‐bismuthate(III) polyhedra that join corners, edges, and faces. The copper(I) cations are spread over numerous contiguous trigonal or tetrahedral voids. In case of (II) a continuous pathway for copper ion transport along [010] is formed. The pseudo‐potential barrier for hopping of copper ions was calculated as 30 meV only. 相似文献
77.
Günther A Heise M Wagner FR Ruck M 《Angewandte Chemie (International ed. in English)》2011,50(42):9987-9990
Te for 10: A tricyclic Te(10) molecule is stabilized in an iridium complex. Bonding analysis reveals 3-center-4-electron bonds in the linear Te(3) fragment. The tellurium atoms act as 2-electron donors to the transition-metal atoms. 相似文献
78.
E Ahmed J Beck J Daniels T Doert SJ Eck A Heerwig A Isaeva S Lidin M Ruck W Schnelle A Stankowski 《Angewandte Chemie (International ed. in English)》2012,51(32):8106-8109
One-dimensional conductor: Strong π?interactions between ecliptically stacked tellurium squares in Te(4) [Bi(0.74) Cl(4) ] trigger excellent one-dimensional metallic conductivity as well as superconductivity below 7.15?K under ambient pressure. The electron-precise counterpart, Te(4) [Bi(0.67) Cl(4) ], is a semiconductor. The bismuth content and temperature- dependent competition of intra- and inter-ring bonding account for the electronic conduction. 相似文献
79.
80.
Viktoria Falkowski Alexander Zeugner Anna Isaeva Klaus Wurst Michael Ruck Hubert Huppertz 《无机化学与普通化学杂志》2019,645(14):911-911