Local structure analysis of Li-substituted NaNbO

Yoneda, Yasuhiro   ; Kohara, Shinji*

NaNbO has expected as an end member of unleaded piezoelectric material is a ferroelectric material studied widely. It is considered as the antiferroelectric crystal at room temperature, and the phase transition of 3 times is shown by the melting point from room temperature. Although the structure of the antiferroelectric phase in room temperature is orthorhombic , the atom position of this structure is very close to rhombohedral . By doping Li, it is possible to also make this hidden rhmbohedral structure appear. We examined the phase transition and the Li dope effect of NaNbO from local order analysis using atomic pair-distribution function (PDF). It is thought that the randomness of site is suppressed by Li like AgNbO, and the structure which is a ferroelectric phase stabilizes NaNbO from the result of local order analysis.