OMIT Instruction

OMIT h k l

The reflection h k l is flagged as 'unobserved' in the list of merged reflections after data reduction. Since there may be perfectly justified reasons for ignoring individual reflections (e.g. when a reflection is truncated by the beam stop) this form of OMIT is allowed with ACTA; however it should not be used indiscriminately. OMIT takes effect after MERG, so if the default MERG 2 is used, OMIT must refer to the indices in the final reflection list, not necessarily as input. It will always be safe to use the indices as given in the list of reflections which do not agree well that is printed after least-squares refinement; however if no sort-merge is performed, OMIT suppresses all reflections with matching indices.