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1.
New Ternary Phosphides and Arsenides of Cesium and Element of the 8th Transition Metal Group In the ternary systems Cesium/8th transition metal group/5th main group some new compounds were found and investigated. By single crystal measurements CsRh2P2 was found to crystallize in the space group 14/mmm with the lattice constants a = 390.11 pm and c = 1429.36 pm. The new compounds with the formula CsM2X2 (M = Fe, Co, Ru, Rh, Ir; X = P or As) crystallize in the ThCr2Si2-type structure, compounds of the formula Cs2MX2 (M = Ni, Pd, Pt; X = P or As) can be placed in a line with the K2PdP2-type structure. 相似文献
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New Ternary Compounds of Cesium and Elements of the 8th Transition Metal Group and the 5th Main Group In the ternary systems Cesium/element of the 8th transition metal group/element of the 5th main group some new compounds were found and investigated. Compounds of the formula Cs2MX2 (M = Pt, Pd, Ni; X = P, Sb, Bi) can be placed in a line with the K2PdP2-type structure. The new compound with the formula CsFe2Sb2 crystallizes in the ThCr2Si2-type structure. By single crystal measurements CsFe2As2 was found to crystallize in the space group I4/mmm with the lattice constants a = 389.43 pm and c = 1 509.97 pm. 相似文献
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Novel Ternary Phases of Platinum Metals with Lithium and Main Group IV Elements The elements palladium, platinum, and iridium (Me) form ternary compounds with lithium and the elements germanium, tin or lead (X) of the formulas Li2MeX and/or LiMe2X. The lattice constants of the cubic fc. crystallizing compounds see ?Inhaltsübersicht”?. Besides the cubic form of LiPd2Ge there exists a tetragonal structure with a = 6.254 and c = 6.410 Å. X-ray investigations on single crystals showed that LiPd2Ge crystallizes in a Heusler lattice (L21A type), Li2PdSn has a modified Li3Bi structure (L21C type). The homogeneity range between the compositions Li2PdX and LiPd2X was investigated. 相似文献
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New Ternary Copper Pnictides with Modified BaAl4 Type Structures EuCu2As2 (a = 4.215(1) Å, c = 10.185(2) Å) and EuCu2Sb2 (a = 4.504(1) Å, c = 10.824(2) Å) were prepared by heating (900°C) mixtures of CuCl and arsenic (antimony) with europium. The by-products were dissolved by dilute acetic acid. The arsenide crystallizes in the ThCr2Si2 type structure (I4/mmm; Z = 2) with holes in the copper arrangement, whereas the antimonide forms the CaBe2Ge2 type structure (P4/nmm; Z = 2). The stability ranges of both phases were determined by mixed crystal formation in accordance with EuCu2As2–xSbx. Magnetic measurements showed, that Europium is divalent and that the compounds order magnetically at low temperatures. BaCu2Sb2 (I4/mmm; a = 4.655(1) Å, c = 32.709(6) Å; Z = 6) was prepared by heating a mixture of binary antimonides of barium and copper in a melt of NaCl/KCl. The structure of this compound consists building elements of the CaBe2Ge2 and the ThCr2Si2 type structure. The already known compounds SrCu2As2 and BaCu2As2 were produced in a homogeneous form for the first time and their structures (ThCr2Si2 type) redetermined by means of single crystal X-ray methods. 相似文献
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New Ternary Selenides of Lanthanoides by Reduction of Sesquiselenides The compounds MLn2Se3 (M = Na; Ln = La? Sm) and MLn8Se12 (M = Na, Ca; Ln = La? Sm) were prepared by reduction of the corresponding lanthanide sesquiselenides with sodium and calcium, respectively, for the first time. Further-more MLa8Se12 (M = Sr, Eu) could be obtained in an analogous way. All compounds were characterized by chemical analysis and X-ray powder diffraction. The electronic structures of these compounds were investigated by band structure calculations and magnetic measurements. 相似文献
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Es wird über Darstellung und Kristallstruktur ternärer AMnX-Verbindungen (A ? Li, Na; X ? P, As, Sb, Bi) berichtet. Sie kristallisieren tetragonal in Raumgruppe P4/nmm-D4h7, wobei sich LiMnX und NaMnX durch unterschiedliche Punktlagen der Alkaliatome unterscheiden. Die AMnX-Strukturen werden mit denen verwandter AMX-Verbindungen verglichen (A ? Li, Na, K, Rb; M ? Be, Mg, Zn, Cd; X ? 5b-Element). Ternary Compounds of Lithium and Sodium with Manganese and Elements of the Fifth Main Group Formation and crystal structure of ternary AMnX compounds (A ? Li, Na; X ? P, As, Sb, Bi) are reported. These compounds crystallize in the tetragonal space group P4/nmm-D. The structures of LiMnX and NaMnX differ by the positions of the alkali atoms. Structural relationship to AMX compounds (A ? Li, Na, K, Rb; M ? Be, Mg, Zn, Cd; X ? 5b element) are discussed. 相似文献
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New Ternary Rhodium‐ and Iridium‐Phosphides and ‐Arsenides with U4Re7Si6 Type Structure Single crystals of Mg4Rh7P6 (a = 7.841(1) Å), Mg4Rh7As6 (a = 8.066(1) Å), Yb4Rh7As6 (a = 8.254(1) Å) and Mg4Ir7As6 (a = 8.082(2) Å) were prepared by heating mixtures of the elements in a lead flux and were investigated by means of X‐ray methods. The compounds are isotypic and they crystallize in the U4Re7Si6 type structure (Im 3 m; Z = 2), which is formed by CeMg2Si2 analogous units, which are twisted against each other. The Rh(Ir) atoms building these units are coordinated tetrahedrally by the non‐metal. The P(As) atoms of six units form a regular octahedron, which is centred by an additional Rh(Ir) atom. This second structural segment corresponds to the perovskit type structure. 相似文献
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On Ternary Thallium Chalcogenides with Thallium Selenide Structure. By means of single crystal investigations, it has been confirmed that the compounds TlGaTe2, TIInSe2, and TIInTe2 crystallize in the TISe type (B37). As an univalent cation thallium is surrounded by eight chalcogen atoms. Gallium and indium are trivalent with tetrahedral coordination and covalent bonds. The interatomic distances as well as coordination and bonding resulting from them are discussed. 相似文献
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Ternary Germanides of Lithium and Rare-Earth-Metals with Fe2P-Type Structure: LiErGe, LiHoGe, LiNdGe and LiSmGe In the systems Li? M? Ge (M ? Er, Ho, Nd, Sm) the compounds LiErGe, LiHoGe, LiNdGe and LiSmGe were prepared. They crystallize hexagonally (space group P-6 2m), and a C22-(Fe2P-type) lattice was found. The crystal structure of LiErGe was determined by X-ray single crystal investigation. Structural features of the compounds are discussed in comparison. 相似文献
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Ternary Phosphides and Arsenides of Rhodium and Iridium: Synthesis and Crystal Structures Single crystals of eight new compounds were prepared by heating mixtures of the elements in a lead flux. They were investigated by X‐ray methods. Ca2Ir12P7 (a = 9.512(1), c = 3.923(1) Å)is an additional representative of the Zr2Rh12P7 type structure, micro domains required refinements of the structural parameters in space group P63/m. Ca5Rh19P12 (a = 12.592(1), c = 3.882(1) Å) and Ca5Ir19P12 (a = 12.577(2), c = 3.954(1) Å) crystallize with the Ho5Ni19P12 type structure (P6¯2m; Z = 1), whereas the compounds A6Rh30X19 form a slightly modified structure of the Yb6Co30P19 type. The lattice constants are: Ca6Rh30P19: a = 15.532(1) Å, c = 3.784(1) Å Sr6Rh30As19: a = 16.135(2) Å, c = 3.916(1) Å Eu6Rh30P19: a = 15.566(1) Å, c = 3.821(1) Å Eu6Rh30As19: a = 16.124(1) Å, c =5 3.903(3) Å Yb6Rh30P19: a = 5 15.508(1) Å, c =5 3.770(1) Å Because one of the four non‐metal atoms, located on different crystallographic sites, is disordered along [001] micro domains are formed. Therefore the parameters were not refined in space group P6¯ (Yb6Rh30P19 type), but in space group P63/m. The metal:non‐metal ratio of all compounds is in the range of 2:1. Accordingly most of the non‐metal atoms are coordinated by nine metal atoms, which form tricapped trigonal prisms. These polyhedra are combined with each other in a different way. 相似文献
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Ternary Intermetallic Phases of Lithium, Transition Metals of the 4th Group and Elements of the 5th Maingroup with Statistical Metal Distribution in the ?Cation”?-Substructure The results of X-ray investigations and neutron diffraction on new and in some cases already known [1, 2] ternary intermetallic phases of Lithium with transition metals of the 4th group (b) and those of the 5th main group (X = P, As, Sb, Bi) will be reported. They crystallize in a partly ?filled”? antifluorite type structure with a statistical Li/B-distribution in the tetrahedral sites. The structures are obviously stabilized by small amounts of enclosed d-elements. 相似文献
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On Ternary Chalcogenides. XXIV. The Structure of TlGaSe2 TlGaSe2 is monoclinic with a = 10.772(3), b = 10.771(5), c = 15.636(8) Å, ß = 100.6(3)°, Z = 16, space group Cc. The refinement yielded an R value of 0.082 for 1366 unique observed reflections (MoKα). The compound crystallizes with a layer structure with two anion layers perpendicular to c* in the unit cell. The structural motive of the layers are large corner-linked Ga4Se10- tetraeder consisting of four corner-linked GaSe4 tetrahedra. Two adjacent layers are turned relative to each other by 90°. They are kept together by Tl1+ ions, which are situated on straight lines parallel to the edges of the Ga4Se10 groups. They are surrounded by six selenium atoms forming trigonal-prismatic TlSe6 polyhedra. 42 screw-axes within the layers are the reason for a strongly pronounced pseudo tetragonal symmetry. Different possibilities of stacking cause a onedimensional disorder along the c* direction. The relations between the TlGaSe2 type and the TlSe type and also the high-pressure modifications of some compounds with the TlGaSe2 structure are discussed. 相似文献
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Ba8Cu16P30 – a New Ternary Variant of the Clathrate I Type Structure Ba8Cu16P30 (a = 14.117(1) Å, b = 10.093(1) Å, c = 28.022(2) Å) was prepared by heating a mixture of the elements (800°C; excess of Ba and P; removal of the by-products by acetic acid/H2O2). The compound crystallizes orthorhombically (Pbcn; Z = 4) in a new superstructure of the cubic clathrate I type structure with an ordered distribution of the atoms. The structure is characterized by a three-dimensional framework of CuP4 tetrahedra with cavities in the form of pentagonal dodecahedra and tetrakaidecahedra, which are occupied by the Ba atoms. The compound shows semiconduction, therefore the composition should be Ba8Cu15.5P30.5. 相似文献
16.
New Mixed‐Valence Ternary Bromides and Iodides of Dysprosium and Thulium of the Type A5M3X12 The new ternary mixed‐valence bromides and iodides of dysprosium and thulium Rb5Dy3Br12, Rb5Tm3Br12, K5Dy3I12, K5Tm3I12, Rb5Dy3I12 and Rb5Tm3I12 were obtained by metallothermic reduction of DyBr3, TmBr3, DyI3 and TmI3, respectively, with potassium and rubidium in the presence of the respective alkali metal halides in sealed niobium containers. The crystal structure was determined for the example of K5Dy3I12 (hexagonal, P 6 2m, Z = 1; a = 1446.7(2), c = 473.3(1) pm): DyI6 octahedra are connected via common trans edges to chains. Magnetic measurements on X‐ray pure samples show Curie‐Weiss behaviour at sufficiently high temperatures. Antiferromagnetic coupling occurs at low temperatures. 相似文献
17.
New Ternary Phosphides and Arsenides with a Metal : Non‐Metal Ratio in the Range of 2 : 1 Six new compounds were prepared by heating mixtures of the elements or by reaction of them in a tin(lead) flux. They were investigated by single crystal X‐ray methods. Sc2Ni12P7 (a = 9.013(1), c = 3.590(1) Å) crystallizes in the Zr2Fe12P7 type structure (P6; Z = 1), which is basically built up likewise by Eu2Pd12As7 (a = 10.040(1), c = 4.100(1) Å) and Sr2Rh12P7 (a = 9.626(1), c = 3.844(1) Å), but one of seven non‐metal atoms has a somewhat modified environment and is disordered along [001]. Therefore their crystal structure corresponds to the Ho2Rh12As7 type structure (P63/m; Z = 1). Ca2Ni7P4 (a = 3.703(1), b = 9.209(1), c = 10.378(1) Å) forms the Nd2Ni7P4 type structure (Pmn21; Z = 2), whereas the atomic arrangements of Ca4Rh13As9 (a = 3.903(2), b = 11.221(1), c = 19.411(4) Å) and Sm4Rh13As9 (a = 3.913(2), b = 11.242(6), c = 19.440(6) Å) correspond basically to the Ho4Ir13Ge9 type structure (Pmmn; Z = 2), but the disorder of Rh8 required the occupation of splitting positions. The transition metals have three, four or five neighbouring atoms of phosphorus or arsenic and form together with them three‐dimensional covalent frameworks, of which holes are occupied by the atoms of the electropositive metal. Most of the polyhedra around the P and As atoms respectively consist of trigonal prisms of metal atoms with additional metal atoms capping the rectangular faces of the prisms. This environment ist characteristic for ternary phosphides and arsenides with a metal : non‐metal ratio in the range of 2 : 1. 相似文献
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New Ternary Clathrate Compounds in the Systems Barium–Indium/Zinc/Cadmium–Germanium: Zintl Compounds with Phase Width? By systematic investigations in the systems barium–indium/zinc/cadmium–germanium we found a couple of new electrovalent ternary compounds with A8X46 clathrate (I) type structures. They crystallize cubically in space-group Pm3n. For Ba8In16Ge30 (a = 1 075.8 pm), Ba8Zn8Ge38 (a = 1 082.0 pm) and Ba8Cd8Ge38 (a = 1 096.0 pm) the structures were verified by X-ray single crystal diffraction data. According to valence and bounding distances the new clathrates should be Zintl compounds. Measurements of the temperature dependence of the electrical resistivity proved, that they are indeed semiconductors. A part of the 2B/3B metal atoms can be substituted by germanium. Charge balance will be retained by creation of vacancies in the A8X46 type structures. By phase analysis the limits of the composition range were determined as Ba8In4Ge9[]3Ge30 (a = 1 084.9 pm), Ba8Zn4Ge10[]2Ge30 (a = 1 073.6 pm) and Ba8Cd4Ge10[]2Ge30 (a = 1 082.0 pm). 相似文献