The charge-carrier transport process of perylene is simulated in a single crystal field-effect transistor on the molecular scale by H. Jiang, Y. Zhao, W. Hu, C. Kloc and co-workers. Charge carriers can be transported in different directions, resulting in anisotropy. Atomically-flat, large-sized, 2D organic nanocrystals can be obtained. Based on this ideal structure, 3D models of molecular packing of perylene are made to show possible charge-carrier transport directions. Both experiments and theoretical calculations on page 990 show that the preferred route of intermolecular transport is along the  direction, highlighted in the image with a beam of white light.