Analysis of the 2D SAXS pattern of the colloidal dispersion of magnetotactic bacteria; the magnetic field was applied in horizontal direction (Θ = 0 • ). Left column: Polar plot of the scattering pattern in logarithmic scale (q max = 0.5 nm −1 ). Middle column: Extracted 2D correlation function P (r, ϕ) (r max = 150 nm). Right column: Correlation function along ϕ = 0 • and 90 • .

Determination of the 2D correlation functions by a SVD for a monodisperse ensemble of prolate rotational ellipsoids with an equatorial radius of 50 nm and a polar radius of 150 nm. (a) Ellipsoids are randomly oriented (isotropic ensemble). (b) Ellipsoids are aligned with their polar axis along Θ = 90 • (anisotropic ensemble). Left column: Polar plot of the scattering pattern in logarithmic scale (q max = 0.2 nm −1 ). Middle column: Extracted 2D correlation function P (r, ϕ) (r max = 400 nm). Right column: Correlation function along ϕ = 0 • and 90 • , and in (b) additionally the calculated cross sections for spheres with diameters of 100 nm and 300 nm, respectively.