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Re: multiple NMR models

herbert_bernstein (yaya@aip.org)
Fri, 20 Oct 95 16:15:12 EDT


The question of unique atom numbers is not just a PDB question, but
a serious mmCIF and DDL question.  At present _atom_site.id is the
key for the atom_site category and "must uniquely identify a
record in the ATOM_SITE list"  Certainly you may define a new and
different key instead, but you would be making a major change
in mmCIF in so doing.  You don't re-use an atom number when you have
alternate pisitions for an atom.  It would seem similar in concept
not to re-use them for multiple models.
  -- H. J. Bernstein