Index

Image CIF dictionary (imgCIF) version 3.00.04

_diffrn_radiation.polarizn_source_norm

Definition:

   
     The angle in degrees, as viewed from the specimen, between
     the normal to the polarization plane and the laboratory Y
     axis as defined in the AXIS category.
     Note that this is the angle of polarization of the source
     photons, either directly from a synchrotron beamline or
     from a monochromater.  This differs from the value of
     _diffrn_radiation.polarisn_norm
     in that _diffrn_radiation.polarisn_norm refers to
     polarization relative to the diffraction plane rather than
     to the laboratory axis system.
     In the case of an unpolarized beam, or a beam with true
     circular polarization, in which no single plane of
     polarization can be determined, the plane should be taken
     as the XZ plane and the angle as 0.
     See _diffrn_radiation.polarizn_source_ratio.

Type: Real

Units: degrees

Category:
diffrn_radiation