Quantitative High-Dynamic-Range Electron Diffraction of Polar Nanodomains in Pb<sub>2</sub> ScTaO<sub>6</sub>.

Peters, Jonathan J P; Sanchez, Ana M; Walker, David; Whatmore, Roger; Beanland, Richard · Adv Mater · 2019

basic_science · Level V

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Abstract

Highly B-site ordered Pb<sub>2</sub> ScTaO<sub>6</sub> crystals are studied as a function of temperature via dielectric spectroscopy and in situ high-dynamic-range electron diffraction. The degree of ordering is examined on the local and macroscopic scale and is determined to be 76%. Novel analysis of the electron diffraction patterns provides structural information with two types of antiferroelectric displacements determined to be present in the polar structure. It is then found that a low-temperature transition occurs on cooling at ≈210 K that is not present on heating. This phenomenon is discussed in terms of the freezing of dynamic polar nanodomains where a high density of domain walls creates a metastable state.