X-ray dichroism and anomalous scattering of potassium tetrachloroplatinate(II)

X-ray dichroism is observed at the L absorption edges of Pt in K₂PtCl₄, and the anomalous scattering tensor for Pt in this square-planar complex is measured in experiments with linearly polarized synchrotron radiation. For special azimuthal settings the diffraction intensities of some reflections depend on only one or the other of the principal values of the tensor. The polarization anisotropy, which is as much as 10 electrons atom^-1 for f”, is the largest yet reported for anomalous scattering. These phenomena offer a new way to determine diffraction phases, but add complications for previous methods using multiple wavelengths.