Data items in the PHASING_MIR category record details about
the phasing of the structure, when methods involving isomorphous
replacement are involved.
All isomorphous based techniques are subsumed in this category,
including single isomorphous replacement (SIR), multiple
isomorphous replacement (MIR), single or multiple isomorphous
replacement plus anomalous scattering (SIRAS, MIRAS).
_phasing_MIR.method
; Standard phase refinement (Blow & Crick, 1959)
;