HRTEM image of ∊16 taken along the b axis. The Fourier transform of the HRTEM image, a symmetry-imposed image (left) and a simulated image (right) are inserted. There is only one mirror symmetry, perpendicular to the c axis. Unit cells are marked and the banana-shaped tile and the pentagonal tile are outlined in the symmetry-imposed image. The simulation was carrried out with −25 nm defocus and 6.6 nm thickness.