Concerted proton transfer from the interfacial water to a phosphate group.

This is observed after about 9 ps in the ab initio MD simulation of DOPC-2 system. Atom color scheme is the same as in Fig 1. The water wire utilized is highlighted in blue. The proton-accepting phosphate moiety is spheres. Other water and lipid molecules are shown as sticks. Note W1 to W4 correspond to O(1) to O(4) in Fig 2.