Extended Data Fig. 6: Statistical analysis of bond length and bond angle from the HRTEM along the [\(2\bar{1}\bar{1}0\)] zone axis.
![Extended Data Fig. 6: Statistical analysis of bond length and bond angle from the HRTEM along the [
$$2\bar{1}\bar{1}0$$
2
1
¯
1
¯
0
] zone axis.](http://media.springernature.com/full/springer-static/esm/art%3A10.1038%2Fs41586-025-09343-x/MediaObjects/41586_2025_9343_Fig10_ESM.jpg?as=webp)
A shorter (red) bond length 1.50 ± 0.08 Å along the (0001) direction and a longer (blue) bond length 1.58 ± 0.05 Å along the [0, 8, \(\bar{8}\), \(\bar{3}\)] direction was retrieved from 20 pairs and 18 pairs C–C distance, respectively, using the Laplacian of Gaussian blob detection algorithm implemented in the scikit-image package. A relatively larger bond angle distribution with an average of 112.1 ± 2.8° was obtained. To verify the accuracy of atomic position identification, the d-spacing values of the (\(01\bar{1}0\)) and (0001) planes (labelled with yellow dashed lines) were analysed to be 2.175 ± 0.063 Å and 2.080 ± 0.030 Å, averaged from the distances between 36 and 32 atom pairs, respectively, which match the d-spacing values from XRD measurement very well.
