Macromolecular dictionary (mmCIF) version 2.0.09

_phasing_MIR_der_site.atom_type_symbol

Definition:

   This data item is a pointer to _atom_type.symbol in the
   ATOM_TYPE category.

   The scattering factors referenced via this data item should be
   those used in the refinement of the heavy-atom data; in some
   cases this is the scattering factor for the single heavy
   atom, in other cases these are the scattering factors for an
   atomic cluster.

Mandatory item: yes