Macromolecular dictionary (mmCIF) version 2.0.09
Polarization ratio of the diffraction beam incident on the crystal. This is the ratio of the perpendicularly polarized to the parallel-polarized component of the radiation. The perpendicular component forms an angle of _diffrn_radiation.polarisn_norm to the normal to the diffraction plane of the sample (i.e. the plane containing the incident and reflected beams).
Mandatory item: noAlias:
_diffrn_radiation_polarisn_ratio (cif_core.dic version 2.0.1)
The permitted range is [0.0, infinity)