Figure 2

(a) A high magnified STEM image corresponding to the framed area I in Fig. 1(a) and the corresponding Fast Fourier Transform (FFT), inset in Fig. 2(a), demonstrating the upper and lower part exhibiting the twinning orientation relationship. (b) High-resolution STEM image of rugged twin boundary formed by segments of LPSOs, showing periodic dislocations along the interface. The GPA strain map (c) parallel with (
) and (d) perpendicular to (
) the LPSO-twin interface in (b), exhibiting misfit dislocation cores with sharp strain gradient.