Cr1.45Tl1.87Mo15Se19, a monoclinic variant of the hexagonal In3Mo15Se19 type

The monoclinic compound Cr_1.45Tl_1.87Mo₁₅Se₁₉ (chromium thallium pentadecamolybdenum nonadecaselenide) represents a variant of the hexagonal In₃Mo₁₅Se₁₉ structure type. Its crystal structure consists of an equal mixture of Mo₆Se₈Se₆ and Mo₉Se₁₁Se₆ cluster units. The Mo and Se atoms of the median plane of the Mo₉Se₁₁Se₆ unit, as well as three Cr ions, lie on sites with m symmetry (Wyckoff site 2e). The fourth Cr ion is in a 2b Wyckoff position with site symmetry.     

Rb4Mo21Se24 containing Mo12 and Mo15 clusters

Rubidium molybdenum selenide, Rb₄Mo₂₁Se₂₄, crystallizes in the trigonal space group R. Its crystal structure consists of a mixture of Mo₁₂Se₁₄Se₆ and Mo₁₅Se₁₇Se₆ cluster units in a 1:2 ratio. Both units are interconnected through Mo—Se bonds. The Rb⁺ cations occupy large voids between the different cluster units.     

Darstellung und Kristallstruktur der Dialkalimetalltrichalkogenide Rb2S3, Rb2Se3, Cs2S3 und Cs2Se3

Preparation and Crystal Structure of the Dialkali Metal Trichalcogenides Rb₂S₃, Rb₂Se₃, Cs₂S₃, and Cs₂Se₃ Crystalline products were obtained by the reaction of the pure alkali metals with the chalcogens in the molar ratio 2:3 in liquid ammonia at pressures up to 3000 bar and temperatures around 600 K. The substances crystallize in the K₂S₃ type structure (space group Cmc2₁(NO. 36)). Unit cell constants see ?Inhaltsübersicht”?. The characteristic feature of this structure are bent polyanions X₃^2?:(X = S,Se). The new described compounds are compared with the other known alkali metal trichalcogenides.     

Cs2Mo15S19: a novel ternary reduced molybdenum sulfide containing Mo6 and Mo9 clusters

The crystal structure of dicaesium pentadecamolybdenum nonadeca­sulfide, Cs₂Mo₁₅S₁₉, consists of a mixture of Mo₆S₈S₆ and Mo₉S₁₁S₆ cluster units in a 1:1 ratio. Both units are interconnected via inter‐unit Mo—S bonds. The Cs⁺ cations occupy large voids between the different cluster units. The Cs and two inner S atoms lie on sites with 3 symmetry (Wyckoff site 12c) and the Mo and S atoms of the median plane of the Mo₉S₁₁S₆ cluster unit on sites with 2 symmetry (Wyckoff site 18e).     

Ag2.54Tl2Mo12Se15: a new structure type containing Mo6 and Mo9 clusters

The novel structure‐type Ag_2.54Tl₂Mo₁₂Se₁₅ (silver thallium molybdenum selenide) is built up of Mo₆Seⁱ₈Se^a₆ and Mo₉Seⁱ₁₁Se^a₆ cluster units in a 1:2 ratio, which are three‐dimensionally connected to form the Mo–Se network. The Ag and Tl cations are distributed in several voids within the cluster network. Three of the seven independent Se atoms and one Tl atom lie on sites with 3.. symmetry (Wyckoff sites 2c or 2d).     

Synthese und Kristallstruktur von Cs3Y7Se12

Synthesis and Crystal Structure of Cs₃Y₇Se₁₂ The oxidation of yttrium metal with selenium in the presence of CsCl (7 d, 700°C, evacuated silicia tubes) results in the formation of pale yellow, lath-shaped single crystals of Cs₃Y₇Se₁₂. The crystal structure (orthorhombic, Pnnm, Z = 2, a = 1272.8(3), b = 2627.7(5), c = 413.32(8) pm) consists of edge- and vertex-connected [YSe₆] octahedra forming a rocksalt-related network [Y₇Se₁₂]^3?. One-dimensional infinite channels along [001], apt to take up extra cations, provide coordination numbers of 6 and 7 + 1, respectively, for two crystallographically different Cs⁺.     

Rb5Mo27Se31, a novel ternary reduced molybdenum selenide containing Mo12 and Mo15 clusters

The crystal structure of Rb₅Mo₂₇Se₃₁, penta­rubidium hepta­cosa­molybdenum hentria­conta­selenium, consists of a mixture of Mo₁₂Se₁₄Se₆ and Mo₁₅Se₁₇Se₆ cluster units in a 1:1 ratio. Both types of cluster are interconnected through inter‐unit Mo—Se bonds. Rb⁺ cations occupy large voids between the different cluster units.     

Methanolothermal Synthesis and Structures of the Quaternary Group 14 – Group 15 Cesium Selenidometalates Cs3AsGeSe5 and Cs4Ge2Se6

Cs₃AsGeSe₅ and Cs₄Ge₂Se₆ can be prepared by methanolothermal reaction of elemental As, Ge and Se with Cs₂CO₃ at 190 °C. The former quaternary phase contains zweier [{AsGeSe₅}^3?] chains consisting of corner‐bridged GeSe₄ tetrahedra and AsSe₃ pyramids and represents the first Ge^IV‐As^III chalcogenidometalate. Cs₄Ge₂Se₆ exhibits discrete [Ge₂Se₆]^4? anions formed by two edge‐sharing GeSe₄ tetrahedra.     

Supercubooctahedron (Cs6Cl)2Cs5[Ga15Ge9Se48] Exhibiting Both Cation and Anion Exchange

A novel type of supertetrahedral connectivity is exhibited by the 72‐atom discrete supercubooctahedron in (Cs₆Cl)₂Cs₅[Ga₁₅Ge₉Se₄₈] ( 1 ), which undergoes both cation and anion exchange, as revealed by unambiguous single‐crystal X‐ray diffraction data. Electronic‐structure studies helped to understand the Ge/Ga distribution.     

Synthesis and structural characterization of quaternary thorium selenophosphates: A2ThP3Se9 (A = K, Rb) and Cs4Th2P5Se17

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.     

Syntheses of the Mo–Ag–Se complexes with a cubane-like core {MoAg3Se3X} (X=Cl and Br). Crystal structures of {MoAg3 Se3Cl}(PPh3)3Se and {MoAg3Se3Br}(PPh3)3Se·0.5Ph3PSe·

Transition Metal Chemistry -     

硒钼钒杂多配合物的合成与表征

由钒原子取代杂多阴离子中的钼或钨原子后,形成的多元配合物具有与原来杂多配合物显著不同的催化性质,有关钼钒的同多阴离子,近年报道的有[V2Mo6O26]^6-、[V5Mo8O40]^7-、[V8Mo4O36]^8-等,而三元硒钼钒杂多分配物仅见于[Se2Mo2V6O28]^6-。本文合成了两种硒钼钒三元杂多配合物,并对其进行了表征。     

Die Kristallstruktur von Cs2S. mit einer Bemerkung über Cs2Se,Cs2Te,Rb2Se und Rb2Te

The Crystal Structure of Cs₂S and a Remark about Cs₂Se, Cs₂Te, Rb₂Se, and Rb₂Te Cs₂S crystallizes orthorhombic, a = 8.57₁, b = 5.38₃, c = 10.3₉ Å, Z = 4, d_rö = 4.13, d_pyk = 4.19 g · cm^?3, D–Pnma with \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {{\rm Cs}}\limits^|,\mathop {{\rm Cs}}\limits^\parallel $\end{document} and S in 4(c) each, for parameter see text. It is R = 10,4% for 202 of 222 possible reflexes. There is a sequence of S^2? corresponding to the hexagonal closest packing of sphares. Cs occupies half of “tetrahedron” and all “octahedron vacancies”; the deviation of \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {{\rm Cs}}\limits^|, $\end{document} in ?oktahedron vacancies”? is noticeable. Effective Coordination Numbers, ECoN, and the Madelung Part of Lattice Energy, MAPLE, are calculated and discussed.