Fig. 5: Comparison between the experimentally observed structure distortion and the relaxed structure model from DFT calculations.
a Reconstructed iCoM image of domain A with clear polyhedral rotation and b the relaxed structure model with F intercalation at apical sites. The red dashed lines in a mark the anion sublattice distortion. c A simulated iCoM image of the structure in b. d Reconstructed iCoM image of domain B showing a clear zigzag arrangement of Nd atoms and e the relaxed structure model with F intercalation at apical sites. f A simulated iCoM image of the structure in e. The blue arrows indicate the displacement direction of the Nd atoms and the red dashed line marks the anion sublattice without distortion in d. g A relaxed structural model with two connected domains. Domain B is formed by a 90o rotation of domain A. h Reconstructed iCoM image of the domain interface and i the enlarged structural model. j A simulated iCoM image of the structure in i. The blue arrows indicate the displacement direction of the Nd atoms and the red dashed line marks the anion sublattice distortion in h. k Reconstructed iCoM image of the region with abnormal structure distortion and l the structure model from the DFT calculations with partial intercalation of F-ions at the basal sites. m A simulated iCoM image of the structure in l. The blue arrows indicate the displacement direction of the Nd atoms and the red dashed line marks the anion sublattice distortion in k. The white lines of the scale bar represent a length of 0.5 nm in the figures.
