Table 1. Fit results for neutron reflectivity performed on OTS against different water subphases.
| Subphase | Combined average thickness,  , Å |
Reduced water density region offset, δ ± 0.5, Å | Width of the error-function profile, σ, Å |
|---|---|---|---|
| Untreated (naturally aerated) D2O | |||
| (a) | 34.8 | 11.3 | 3.6 ± 0.3 |
| (b) | 33.7 | 10.3 | 3.2 ± 0.5 |
| (c) | 31.0 | 7.6 | 3.4 ± 0.2 |
| Ar D2O | 26.5 | 2.0 | 4.2 ± 0.3 |
| CO2 D2O | 28.8 | 5.8 | 3.7 ± 0.8 |
| Before degassing | 31.0 | 7.6 | 3.4 ± 0.2 |
| Vacuum degassed D2O | |||
| T = 0 hr | 28.6 | 5.2 | 2.1 ± 0.2 |
| T = 5 hr | 29.1 | 5.7 | 2.9 ± 0.6 |
| T = 18 hr | 30.3 | 6.2 | 4.2 ± 0.1 |
δ and σ were obtained from Parratt fitting algorithm (see text for details). The errors on these parameters are based on a single parameter error analysis (χ2 → χ2 + 1); all δ have a maximum error of 0.5 Å.