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IR Spectra and Forcefields of Ternary Alkali–Yttrium Fluorides with Elpasolite Structure IR spectra of A2BYF6 are reported and five force constants are calculated using a modified valence force field. The results are discussed with respect to the two bond characters.  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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Reaction of F3B · NH(CH3)2 with PCl5 yields [(CH3)2NPCl3][BCl4] (I), which can also be obtained by reaction of [(CH3)2NBCl2]2 with PCl5. In BF3 · N(CH3)3 the fluorine atoms are exchanged with chlorine atoms, by PCl5, 31P, 19F, and 11B-NMR spectra of the reactions products are described and discussed.  相似文献   

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Mass Spectrometrical Investigations of Binary Mixtures Alkali Halide – Alkaline Earth Halide The vapor composition of some binary mixtures alkali halide – alkaline earth halide was investigated by high-temperature mass spectrometry. Concentrations of all molecules in gas phase in dependence on the molar composition of liquid mixture were studied. In the vapors over all mixtures exist gaseous heterocomplexes. With increasing radius of the anion a tendency of decreasing stabilities of 1:1 heterocomplexes is stated. The absolute content of gaseous complexes is a function of the ratio of the vapor pressures of the pure components of mixtures. Calculated formation enthalpies fo various stoichiometric heterocomplexes are given.  相似文献   

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Phase Diagrams and Enthalpies of Mixing of Some Binary Systems with Silver Chloride The phase diagrams AgCl + SrCl2, AgCl + BaCl2, AgCl + HgCl2, AgCl + PdCl2, AgCl + CdCl2, AgCl + InCl3, and AgCl + YCl3 were determined by differential thermal analysis and x-ray methods. The first three systems are simple eutectic, in the remaining four systems the compounds Ag3InCl6, Ag3YCl6, and Ag2PdCl4 were found, additionaly two further phases of so far unknown composition were obtained in the systems AgCl + PdCl2 and AgCl + CdCl2. The enthalpies of mixing of molten AgCl + SrCl2 and AgCl + CdCl2 were determined.  相似文献   

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Crystal Structures and Spectroscopic Investigations of Ternary CuII-Complexes with Bicyclic Dicarboxylic Acids and N,N-Donor Ligands The synthesis of coordination compounds [CuLdam] · 3H2O (H2L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) and its 1-methyl-derivative ( 2 ); dam = ethylendiamine, 1,2- and 1,3-propylendiamine, 2,2′-dipyridyl, 1,10-phenanthroline) has been described. Results of visible and IR spectroscopy and magnetic data are given. In the result of X-ray analyses of [CuL1dipy] · 3H2O ( 1 d ) and [CuL2en] · 3H2O ( 2 a ) the dicarboxylate anions of 1 and 2 proved to be tridentate chelating ligands. In 1 d the Cu atom has an approximately square-pyramidal coordination with the bridging O atom in the apical position. In 2 a , however, the coordination number is extended to six by an O atom of a second [CuL2en] unit resulting in a centrosymmetric complex dimer with octahedrally coordinated Cu atoms. The water molecules do not participate in the coordination of the Cu atoms and form a complicated system of hydrogen bonds in the crystal.  相似文献   

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Contributions to the Chemical Transport of Metal Oxides. V. Transport of Ternary and Quaternary Mixed Ferrites by their Chlorides The transport by means of HCl as transporting gas in a closed system in the case of the ternary mixed ferrites (Ni0,8Fe2,2O4, Mn0,75Fe2,25O4, Mn1,286Fe1,714O4) and the quaternary mixed ferrites (Mg0,5Mn0,5Fe2O4, Mg0,75Mn0,536Fe1,714O4, Mg0,281Mn0,469Fe2,25O4, Mn0,5Zn0,5Fe2O4, Mn0,5Zn0,45Fe2,05O4, Ni0,5Zn0,5Fe2O4) between T2 = 1100?1000°C and T1 = 1000?800°C was investigated. Transported crystals were characterized by chemical analysis and the saturation magnetization, the transport rate has been checked. In the case of Mn0,5Zn0,45Fe2,05O4 two phases were transported. By discussing the phase diagram an explanation is given.  相似文献   

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