| 1. |
- Dinnebier, R., et al.
(författare)
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Crystal structures of the trifluoromethyl sulfonates M(SO3CF3)(2) (M = Mg, Ca, Ba, Zn, Cu) from synchrotron X-ray powder diffraction data
- 2006
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Ingår i: Acta Crystallographica Section B. - 0108-7681 .- 1600-5740. ; 62, s. 467-473
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Tidskriftsartikel (refereegranskat)abstract
- The crystal structures of divalent metal salts of trifluoromethyl sulfonic acid ('trifluoromethyl sulfonates') M( SO3CF3)(2) (M = Mg, Ca, Ba, Zn, Cu) were determined from high-resolution X-ray powder diffraction data. Magnesium, calcium and zinc trifluoromethyl sulfonate crystallize in the rhombohedral space group R (3) over bar . Barium trifluoromethyl sulfonate crystallizes in the monoclinic space group I2= a(C2/c) and copper trifluoromethyl sulfonate crystallizes in the triclinic group P (1) over bar. Within the crystal structures the trifluoromethyl sulfonate anions are arranged in double layers with the apolar CF3 groups pointing towards each other. The cations are located next to the SO3 groups. The symmetry relations between the different crystal structures have been analysed.
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| 2. |
- Dinnebier, R E, et al.
(författare)
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Effect of crystal packing on the structures of polymeric metallocenes
- 2005
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 1520-510X .- 0020-1669. ; 44:4, s. 964-968
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Tidskriftsartikel (refereegranskat)abstract
- The pressure dependencies of the crystal structures of the polymeric metallocenes lithium cyclopentadienide (LiCp) and potassium cyclopentadienide (KCp) have been determined by synchrotron X-ray powder diffraction. The decrease of the volume of LiCp by 34% up to a pressure of p = 12.2 GPa and of KCp by 23% at p = 5.3 GPa as well as the bulk moduli of K = 7.7 GPa for LiCp and 4.9 GPa for KCp indicate a high compressibility for these compounds. The crystal structures of KCp have been determined up to p = 3.9 GPa. An increase of the bend angle is found from 450 at P = 0 GPa up to 510 at p = 3.9 GPa. This variation is completely explained by a model invoking attractive K+ Cp- interaction and repulsive nonbonded carbon-carbon interactions. It is proposed that the bend angle in the polymeric alkali metal metallocenes is the result of the optimization of the crystal packing.
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| 3. |
- Hildebrandt, Lars, et al.
(författare)
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Crystal structure and ionic conductivity of cesium trifluoromethyl sulfonate, CSSO3CF3
- 2005
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Ingår i: Zeitschrift für Anorganische und Allgemeines Chemie. - : Wiley. - 0044-2313 .- 1521-3749. ; 631:9, s. 1660-1666
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Tidskriftsartikel (refereegranskat)abstract
- The crystal structures of the room and the high temperature modifications of cesium trifluoromethyl sulfonate were solved from high resolution X-ray powder diffraction data. At room temperature, alpha-CsSO3CF3 crystallizes in the monoclinic space group P2(1) with lattice parameters a = 9.7406(2) angstrom, b = 6.1640(1) angstrom, c = 5.4798(1) angstrom, and beta = 104.998(1)degrees; Z = 2. At temperatures above T = 380 K, a second order phase transformation towards a disordered C-centered orthorhombic phase in space group Cmcm occurs with lattice parameters at T = 492 K of a = 5.5074(3) angstrom, b = 19.4346(14) angstrom, and c = 6.2978(4) angstrom; Z = 4. Within the crystal structures, the triflate anions are arranged in double layers with the apolar CF3-groups pointing towards each other. The cesium ions are located between the SO3-groups. CsSO3CF3 shows a specific ion conductivity ranging from sigma = 1.06 center dot 10(-8) Scm(-1) at T = 393 K to sigma = 5.18 center dot 10(-4) Scm(-1) at T = 519 K.
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| 4. |
- Hildebrandt, Lars, et al.
(författare)
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Crystal structure and ionic conductivity of three polymorphic phases of rubidium trifluoromethyl sulfonate, RbSO3CF3
- 2006
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 45:8, s. 3217-3223
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Tidskriftsartikel (refereegranskat)abstract
- The crystal structures of three polymorphic phases of rubidium trifluoromethyl sulfonate (RbSO3CF3, rubidium 'triflate') were solved from X-ray powder diffraction data. At room temperature, rubidium triflate crystallizes in the monoclinic space group Cm with lattice parameters of a = 19.9611(5) angstrom, b = 23.49113(7) angstrom, c = 5.1514(2) angstrom, beta = 102.758(2)degrees; Z = 16. At T = 321 K, a first-order phase transition occurs toward a monoclinic phase in space group P2(1) with lattice parameters at T = 344 K of a = 10,3434(5) angstrom, b = 5.8283(3) angstrom, c = 5.1982(3) angstrom, beta = 104.278(6)degrees; Z = 2). At T = 461 K, another phase transition, this time of second order, occurs toward an orthorhombic phase in space group Cmcm with lattice parameters at T = 510 K of a = 5.3069(2) angstrom, b = 20.2423(10) angstrom, c = 5.9479(2) angstrom; Z = 4. As a common feature within all three crystal structures of rubidium triflate, the triflate anions are arranged in double layers with the lipophilic CF3 groups facing each other. The rubidium ions are located between the SO3 groups. The general packing is similar to the packing in cesium triflate. Rubidium triflate can be classified as a solid electrolyte with a specific ionic conductivity of sigma = 9.89 x 10(-9) S/cm at T = 384 K and sigma = 3.84 x 10(-6) S/cm at T = 481 K.
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