We also found from the present DFT calculations that the interlayer ESP becomes structureless as the interlayer distance dint increases from its optimal value dint(opt). Figure shows a variation in the ESP with interlayer distance obtained for the cluster with θ = 24.0°, which is characterized by dint(opt) = 0.329 nm. One sees from Fig. that the positive ESP almost disappears for dint=0.375 nm, and the interlayer ESP eventually becomes almost structureless for din=0.475 nm. This probably accounts for the reason why in previous HRTEM studies on MSLs, the extra FFT diffraction spots, such as those observed in Fig. , have not been reported to occur. In the previous HRTEM measurements, it is likely that various adsorbates are trapped between layers during their assembly and sample handling, which prevents the observation of interlayer moiré potential. Thus, as mentioned repeatedly before, the preparation of adsorbate-free samples is a prerequisite to observe moiré potential as FFT diffraction spots. The chemical exfoliation procedure developed in this work is one useful method for obtaining clean hBN nanolayers and hence observing their moiré potential. We are now applying the present method to graphite and transition metal dichalcogenides. Currently, studies are in progress to confirm its applicability to other vdW systems.