Figure and c were then analysed using the 1D PSDF function in Gwyddion to obtain the wavenumber for each sample, calculated from the peaks shown in Figure and e. Cross sectional analysis was carried out by extracting profiles along the dotted line, shown as an example in Figure . These were taking along the horizontal lattice axis, averaged across a thickness of 5 nm to reduce line to line variations. Images were exported using Gwuddion, and PSDF and cross sectional analysis data plotted using Matplotlib and Seaborn libraries in Python.