checkCIF procedure

PLAT023

 Check resolution of the data set. This alert is issued when sin(theta)/lambda
 < 0.6 (i.e. theta < 25.24 degree for MoKa or 67.7 degree for CuKa radiation).
 In principle, all observed data should be included in the refinement.
 Alternatively, a sin(theta)/Lambda cutoff value can be used at a value where
 average(I/Sigma(I)) < 2 in order not to refine on noise.