Polarized-Neutron Diffraction from Spin-Polarized Protons: A Tool in Structure Determination?

We have observed the spin-dependent diffraction of slow neutrons by differentially polarized nuclei in single crystals of lanthanum magnesium nitrate. The effects are accompanied by enhanced Bragg diffraction and reduced incoherent scattering at high proton polarizations. The diffraction pattern is very sensitive to selective depolarization of nuclei, and proton resonances have been observed through changes in the diffracted intensities when the sample is irradiated at the Larmor frequencies.