Maximum Entropy Reconstruction of Spin Density Maps in Crystals from Polarized Neutron Diffraction Data

Polarized neutron diffraction essentially measures discrete spatial 3D Fourier components of the magnetization density inside a single crystal, which is known to obey symmetry requirements. Due to restricted and noisy data sets, the standard analysis, which involves the computation of the inverse Fourier transform of the data, often results in heavy truncation and noise effects. The maximum entropy method (MaxEnt) is shown to perform much better: one can now "see" the magnetic moments in the unit cell, or at least their projections along a given crystallographic direction.