Crystal structure and ionic conductivity of cesium trifluoromethyl sulfonate, CsSO3CF3

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, α-CsSO3CF 3 crystallizes in the monoclinic space group P21 with lattice parameters a = 9.7406(2) Å, b = 6.1640(1) Å, c = 5.4798(1) Å, and β = 104.998(1)°; 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) Å, b = 19.4346(14) Å, and c = 6.2978(4) Å; 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. CsSO3CF 3 shows a specific ion conductivity ranging from σ = 1.06-10-8 Scm-1 at T = 393 K to σ = 5.18·10-4 Scm-1 at T = 519 K. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.