Core dictionary (coreCIF) version 2.4.5
Fraction of Laue unique reflections (symmetry-independent in the Laue group) measured out to the resolution given in _diffrn_reflns_resolution_full or _diffrn_reflns_theta_full. The Laue group always contains a centre of symmetry so that the reflection h,k,l is always equivalent to the reflection -h,-k,-l even in space groups without a centre of symmetry. This number should not be less than 0.95, since it represents the fraction of reflections measured in the part of the diffraction pattern that is essentially complete.
The permitted range is 0.95 -> 1.0
Related item: _diffrn_measured_fraction_theta_full (alternate)