where the broad hydrophobic core region is represented by two Gaussians at ±𝑧 𝐶 with similar width of 𝜎 𝐶 and the position of the polar groups are given also by two Gaussians at ±𝑧 𝐻 . The minimum to maximum electron density contrast here is given by 𝜌 𝑅 = 𝜌 𝐶 /𝜌 𝐻 . We note, that adding more fitting parameters (additional Gaussian distributions) to the SAXS model did not statistically improve the fits.