Figure 2
From: Band Structure Engineering and Thermoelectric Properties of Charge-Compensated Filled Skutterudites
STEM analysis and structural modeling.
(a) STEM-HAADF image (convergent angle: 21 mrad, collection angle: 67–275 mrad). The structure model (red, green and blue spheres represent Co, Sb and Ga/Yb atoms, respectively) and calculated image (inset with white outline) are embedded in the image. A line scan intensity profile from the yellow dashed line is shown at the bottom. The green circles pointed by the yellow arrow illustrate the misalignment of the Sb atoms, indicating the distortion of the Sb cage that is associated with the off-center-cage filling behavior of the filler atoms. (b) Intensity line profiles from the experimental image and simulations. The red circles are from the red scan line shown in (a), the light blue and black lines are from the calculations based on the structure models of Yb0.26Ga0.2Co4Sb11.9333 with filled Ga/Yb at center (light blue) and deviated 0.027 nm away from the center (black), respectively. The orange and green lines are from the orange and green scan lines in (a).
