Figure 7.

NMR deuterium order parameters (S_CD) for a hydrated DPPC bilayer. Shown are the S_CD calculated using the new Drude polarizable force field (red), C36 additive force field (blue), and measured from experiments (black). The results for the C36 force field were taken from Klauda et. al.¹⁶ Experimental data were taken from Seelig and co-workers.^66–69 and Strenk et al;⁷⁰ the data for the Sn-2 chain is taken from Douliez and et al.⁷¹ The temperature of the MD simulations and the experimental data is 323 K. The axis labels follow the original naming convention from Seelig, where the glycerol carbon attached to phosphorous is called G3 where the palmitic chains are bonded to carbons 1 and 2 of the glycerol. The CHARMM force field and topology follows the Sundaralingam¹²⁵ notation given by the following: β is C12-H12A and C12-H12B, α is C11-H11A and C11-H11B, G1R is C3-HX, G1S is C3-HY, G2 is C2-HS, G3R is C1-HA, G3S is C1-HB, C2 is C22-H2R and C22-H2S, and C2R is C32-H2X.