  We describe a model-independent approach for the extraction of spin-wave
dispersion curves from neutron total scattering data. The method utilises a
statistical analysis of real-space spin configurations to calculate
spin-dynamical quantities. The RMCProfile implementation of the reverse Monte
Carlo refinement process is used to generate a large ensemble of supercell spin
configurations from powder diffraction data. Our analysis of these
configurations gives spin-wave dispersion curves that agree well with those
determined independently using neutron triple-axis spectroscopic techniques.
