Using pressure, temperature and frequency as variables to study the dynamics of mobile ions in materials with disordered structures

摘要: Complementary ways for studying the motion of mobile ions in materials with disordered structures are obtained by varying pressure, tempe- rature and frequency. New results presented based on a combination experimental work modelling. Pressure-dependent measurements alkali borate glasses show there is remarkable difference between activation volumes conduction diffusion, ΔVσ< ΔVD, implying that Haven ratio decreases increasing pressure. We propose mechanism characterised directionally positive correlation successive hops different into moving vacant site. The effect pressure to increase degree directional thus make pathways increasingly linear aspect. In sodium much lower content, maximum has been observed when ionic conductivity plotted versus temperature at fixed This feature identified as being nearly constant loss (NCL) type, caused localised flip-flop movements interacting charges B2O3 network. crystalline γ-RbAg4I5, related also found, this case activated silver confined within structural “pockets”. Finally, frequency dependence reviewed fragile melts. Fragility interpreted here consequence shape local potentials, which unlike glass do not reflect pre-existence empty cation sites hop into. short-range, short-time behaviour leads directly emergence non-Arrhenius dc fluidity behaviours molten salts. able establish common phenomenological theoretical approach ion transport wide range systems, largely broadband spectroscopy.