Crystal structure and ionic conductivity of three polymorphic phases of rubidium trifluoromethyl sulfonate, RbSO3CF3
2006 (English)In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 45, no 8, 3217-3223 p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
2006. Vol. 45, no 8, 3217-3223 p.
abinitio structure determination, spin-lattice relaxation, powder diffraction data, paddle-wheel mechanism, x-ray, lithium trifluoromethanesulfonate, anion reorientation, percolation model, cation-transport, nuclear
IdentifiersURN: urn:nbn:se:kth:diva-15622ISI: 000236961000015OAI: oai:DiVA.org:kth-15622DiVA: diva2:333664
QC 201005252010-08-052010-08-05Bibliographically approved