For a better understanding of the extra diffraction spots, we analyzed the positions of these spots ke in reciprocal space. It has been revealed that ke can be found by connecting the two Bragg spots belonging to the different layers and translating the obtained vectors to the center of the diffraction pattern, as demonstrated in Fig. . The relationship can be written as ke = G1 G2, where Gi (i = 1, 2) represents the reciprocal vectors from two different layers. This relationship implies that the interlayer interactions are responsible for the generation of these extra diffraction spots indeed, but the question is, why do particular sets of the reciprocal vectors contribute to the extra diffraction processes? Here, one should remind that under WPOA, the contrast in HRTEM images is proportional to the projected specimen potential, convoluted with the impulse response of the instrument. Note, however, that diffraction peaks due to moiré structures (or double diffraction) cannot be observed when acquired at typical TEM electron energies (60300 keV) under WPOA, provided that the projected specimen potential consists only of the potentials of individual atoms in the respective layers (see 'Intensity of moiré peaks in diffraction pattern' section in the Supporting Information). We hence assume that the observed extra diffraction spots are originated from a well-defined moiré potential newly created by interlayer coupling. The moiré potential presumably has complicated spatial distributions and periodicity depending on the twist angle. When an electron beam is diffracted by the interlayer moiré potential, the resulting diffraction pattern will not necessarily have 6-fold rotational symmetry except for the commensurate MSLs but should be represented by the combination of a set of ke vectors with particular frequencies and amplitudes, accounting for the underlying characteristics of the extra diffraction spots with particular frequencies and intensities.