The tail tilt angles of MMG-1 display larger similarity in the non-interdigitated systems to those in the interdigitated structures, with maximum peaks at angles found at 7.5°to 11°(tail 1) and 8.5°to 11°(tail 2). All stereoisomers have similar tail tilt angles in the interdigitated systems with maximum probabilities at 4.5°to 5°(tail 1), and 6°to 7°(tail 1). The difference in tilt angles between the two MMG analogs is most pronounced in the single bilayer structure (Figures We analyzed two splay angles: the C9-C5-C22 splay angle close to the lipid acid moiety (splay 1) and the C20-C5-C35 splay angle, which considers the full length of the tails (splay 2) (Figure ). Both MMG-1 and MMG-6 molecules show similar distributions of splay angles, with three distinct peaks of splay 1. With splay 1, for all the cases, the majority of the lipids have the upper part of their tails forming an angle close to 95°and a second angle close to 120°(Figures ). A small population of angles also exists around 150°. With MMG-6, however, the probability distribution is more evenly spread between the first two peaks. This indicates a higher probability for a larger splay near the area connecting the glycerol and the lipid acid moiety. A larger splay angle means that these lipids are more likely to take up a larger volume within the membrane. Our APL xy and APL vor results support this idea. The probabilities of splay angle 2 show higher similarity between the systems, the majority of the splay angles being close to 15°(Figure ). This angle corresponds to a closed-tail conformation. A second, more subtle, peak can be seen at approximately 27°.