Structure and Conductivity of Nanostructured Sodium Nitrite

Combined neutron diffraction, dielectric and conductivity measurements of NaNO2 embedded into porous glasses with average pore diameter 7 nm are performed in the ferroelectric and paraelectric phases. The temperature interval of existence of a volume premelted state in this confined material is determined. It is shown that the observed earlier giant growth of dielectric constant above TC can be attributed with an appearance of ionic conductivity due to jumping diffusion (or hopping) of constituent ions. These data are in a good agreement with experimental results of our earlier measurements of temperature evolution of structure of this nanocomposite material.

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