Wiedemann, D.; Heppke, E.M.; Franz, A.: And Yet It Moves: A High‐Temperature Neutron Diffraction Study of Ion Diffusion in the Inverse Perovskites BaLiX3 (X = F, H, D). European Journal of Inorganic Chemistry 2019 (2019), p. 5085-5088
Open Accesn Version
Despite the interest in (anti‐)perovskites and diverse hydrides as hydride conductors and all‐solid‐state battery materials, little experimental evidence on anion diffusion in these compounds is available. Herein, we use neutron diffraction at high temperatures to discover pathways and estimate activation barriers of anion migration in mechanosynthesized powders of BaLiF3, BaLiH3, and BaLiD3. We critically assess the limitations of both current methods for deriving effective one‐particle potentials (i.e., via modelling of the probability‐density function and via maximum‐entropy reconstruction of the scatterer density). The suggested migration pathways run roughly along the edges of the LiX6 octahedra with activation energies of 0.45(3), ca. 0.41, and less than 1.44(3) eV in BaLiD3, BaLiH3, and BaLiF3, respectively. Not only is this the first determination of diffusion barriers in these hydrides but also the second study providing any comparative data on the two methods of derivation.