view article
Figure 3
Focal series of single-layer graphene oxide. (a) Orthogonal views of the 2D power spectra near true focus. The inset shows the top left diffraction spot at 2.13 Å, with a periodic variation that reflects the offset of the sphere. (b) Orthogonal views of the 3D power spectrum. In the 3D power spectrum, the two spots fall on the two spheres, offset to a frequency of 0.0027 Å−1 (∼2 pixels). The inset shows the well separated reflections of the top left spot. (c) The six reflection spots on the upper sphere were masked and back transformed, showing oscillations in z consistent with the periodicity in the inset in (a). (d) The whole transform was shifted to the central section (−2 pixels), giving a constant density in the z direction as expected from a simple projection.

IUCrJ
Volume 13| Part 1| January 2026| Pages 77-93
ISSN: 2052-2525
https://doi.org/10.1107/S2052252525010796