Figure 4.
Side profile snapshots from the 512 lipid simulations at 318 K (A) and 317 K (B), either side of (see Fig. 3). (C) A zoomed-in snapshot of the ripple in the 512 lipid, 317 K system shown in (B). All snapshots are colored according the conformational cluster the lipid has been assigned. The ripple phase features two regions, the major arm (solid line) and the minor arm (dashed line). (D–F) Top views of the 317 K system. (D) The sum of the two leaflets; (E and F) the upper and lower leaflet, respectively. The simulation box is indicated in the figures by the box, and periodic images are included for visual clarity. The ripple has an amplitude of 19.2 Å. For comparison, the thickness perpendicular to the major arm (44 Å) is consistent with experimental values for the DPPC gel phase (40), and the tilt in the major arm is also consistent with experiments using DMPC (4,41). The two arms are asymmetric in length, in agreement with experiments and theory (1,2,42,43). To see this figure in color, go online.