Fig. 5: Atomic iDPC-STEM imaging of infinite-layer phase.
From: Atomic scale disorder and reconstruction in bulk infinite-layer nickelates lacking superconductivity
a Structure transition during the topotactic reduction. b iDPC-STEM image of infinite-layer phase at [100] orientation. c–e Enlarged iDPC-STEM images extracted from the orange dotted line box in (b), where the orange arrow marks the residual oxygen atom in the Nd/Sr atomic plane. f Atom model of the distorted NiO2 layers projected in [100] direction. The bond angle and the deviation of Ni atom are marked as well. g The ratio of lattice parameter c/a according to (b). h Statistical data of lattice constants a and c. i The calculated bond angle contour maps are plotted over the iDPC-STEM image. j The histogram displays the statistical data for bond angles measured across multiple regions, with a fitted value of 177.0° ± 5.3°.
