Schwinger and anomalous scattering of neutrons from CdS

Polarization-sensitive neutron scattering from CdS single crystals has been observed for several Bragg reflections. This effect arises from interference between neutron spin-neutron orbit (Schwinger) scattering and 90° phase-shifted scattering due to such sources as absorption and a noncentrosymmetric crystal structure. The observed flipping ratios are in excellent agreement with those calculated on the basis of the accepted conventions for the determination of absolute configuration by X-ray or neutron diffraction. Possible application of the Schwinger scattering to the routine determination of absolute configurations is discussed.