Previous MD simulation work with emollients and disaturated phosphatidylcholines (PC) in the gel phase has exemplified the link between molecular geometry and the overall membrane structure and properties such as tail tilt. For the case of emollients and disaturated PCs, the headgroup size or branching of the tails can result in energetically unfavorable distances between the molecules, and increased tail tilt is required to achieve optimal tail packing.