Structure and vibrational spectra of oxonium hexafluoroarsenates(V) and -antimonates(V)

Abstract

Abstract : The salts OD3(+)ASF6(-), OD3(+)SBF6(-1) and partially deuterated OH3(+)SBF6(-) were prepared and characterized by X-ray and neutron diffraction techniques, DSC measurements, and vibrational spectroscopy. At room temperature, OH3(+)ASF6(-) exists in a plastic phase where ions, centered on the atomic positions of the NaCl structure, are in motion or oscillation. No valuable information on atomic distances or angles in OH3(+)SBF6(-) could be obtained due to these dynamic structural disorder problems. For OH3(+)SBF6(-) the phase transition from an ordered to a disordered phase was shown to occur above room temperature.