Figure 6
(Top) Sparse QENS analysis for different samples using two Voigt functions to fit the energy dependence. A significantly better agreement is observed for high energy transfers, where different diffusive processes contribute substantially to the scattering signal. Fits are shown at q = 1 Å−1 for different maximum energy transfers ℏωmax = 3 µeV (solid blue line), ℏωmax = 5 µeV (orange dotted line), ℏωmax = 7 µeV (green dashed–dotted line) and ℏωmax = 10 µeV (brown dashed line). The different curves are shifted by a factor of ten each for better visibility. (Bottom) The q2 dependence of the corresponding widths of the fit for ℏω < 10 µeV and a fit of γ = Dq2 to determine the diffusion coefficient D. In both plots, blue spheres, magenta pentagons, cyan squares, olive down pointing triangles, red right pointing triangles and green left pointing triangles represent values for BSA 100 mg ml−1 at 280 K, myoglobin 500 mg ml−1 at 280 K, polyclonal IgG 500 mg ml−1 at 280 K, BSA 500 mg ml−1 at 310 K, BSA 500 mg ml−1 at 295 K and BSA 500 mg ml−1 at 280 K, respectively. |