Figure compares the Dvinskikh DMPC data (panel A) to our POPC data (panel B) for the PC headgroup, the glycerol backbone, and the saturated (sn-1 in POPC) tails. For all nonzero S CH , the qualitative response to dehydration is very similar in both lipids: The headgroup S CH increase, the backbone and tail S CH decrease. An exception is the carbon segment g 2 , whose S CH appear insensitive to hydration level in POPC, whereas in DMPC the negative S CH decreases further upon dehydration.