TABLE 2.
Box model fitting scattering length densities for monolayers on H2O
| DPPE:GM1 monolayer
|
With CTB5
|
With CTAB5
|
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Region | Z (Å) | β(z) × 10−6 | σ (Å)* | Z (Å) | β(z) × 10−6 | σ (Å) | Z (Å) | β(z) × 10−6 | σ (Å) |
| Lipid tail | 17.8† | 6.0 ± 0.1 | 4 ± 1† | 17.8† | 5.4 | 4† | 17.8† | 5.7 | 4† |
| Headgroup | 7.5† | 2.0 | 3† | 7.5† | 1.7 | 3† | 7.5† | 1.8 | 3† |
| GM1 | 13.5† | 0.4 | 3† | 8.8 | 0.5 | 3† | 8.1 | 0.68 | 3† |
| CTB5 | 25† | 0.56 | 3† | 25† | 0.36 | 3† | |||
| CTAB5 | 25 | −0.35 | 3 | ||||||
| Subphase | −0.4 | 3† | −0.4† | 3† | −0.4† | 5 | |||
The χ2 values were between 0.75 and 1.02 for box model fits reported in this table.
*
Because our Qz range was limited to 0.24 Å−1, fitted parameters were not very sensitive to small changes in roughness. Due to capillary waves, a minimum roughness of 3 Å was assumed (Braslau et al., 1988).
†
Parameters that were fixed and not allowed to vary during the fitting procedure.