PROC-NAME: SHFSU01 Type_2
PURPOSE: To check that _refine_ls_shift/su_max is within expected limits.
IF |_refine_ls_shift/su_max| > 0.20 issue ALERT A
"Alert A The absolute value of parameter shift to su ratio > 0.20"
> 0.10 issue ALERT B
"Alert B The absolute value of parameter shift to su ratio > 0.10"
> 0.05 issue ALERT C
"Alert C The absolute value of parameter shift to su ratio > 0.05"
IF _refine_ls_shift/esd_max has been used issue General ALERT
An elevated value for the largest parameter shift/s.u. is indicative
that proper convergence of the refinement has not yet been achieved.
Additional cycles of refinement are usually sufficient to achieve
adequate convergence and remove this alert. In disordered or otherwise
poorly behaved structures, many additional cycles may be required before
a suitable level of convergence has been achieved. Any parameters that
remain constantly oscillating should be detailed in the
_publ_section_exptl_refinement section. You should also consider
whether appropriate restraints might help to stabilise ill-defined
and oscillating parameters.
"_refine_ls_shift/esd_max is an old dataname which has been
superceded by _refine_ls_shift/su_max"
IF neither _refine_ls_shift/su_max or _refine_ls_shift/esd_max has been used issue ALERT C
You are using an "old-fashioned", but still legal data name:
_refine_ls_shift/esd_max. Please update the item to match the
currently preferred name of refine_ls_shift/su_max.
To ease this problem for the future, it is recommended that you upgrade
or modify your CIF generating software accordingly.
"Alert C Test not performed. _refine_ls_shift/su_max is not present."
It is compulsory to report the largest parameter shift/s.u. value
in the final refinement cycle under the item _refine_ls_shift/su_max.
This data name is not present in your CIF or has not been assigned
a value. Please insert the data item with an appropriate value.
Full list of validation algorithms
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