Discussion List Archives

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: coreCIFchem #5

Thak you Howard for your careful and thoughtful analysis of dicussion 
#5.  In the fullness of time I will compare this with other submissions 
and come up with a more refined proposal.  At this point I would like to 
comment on only one item:

>  One of the aspects of David's implementation as seen in the TNT example which troubles me, is the necessity for each atom in each molecule to have an unique identifier as coded in '_molecular_unit_atom_mu_id'. As far as I remember there are already several million molecules that are known and giving every atom in each molecule a unique identifier is cumbersome to say the least. 
The identifier only has to be unique within this list.  It is one of the 
CIF management features that allows every line in every list in a CIF to 
be individually addressed.  It acts as a parent to other items so that 
each list can refer as needed to other lists in the CIF.  The uniqueness 
does not extend beyond the current CIF and nothing in my proposal 
addresses the question of locating items that may be in databases 
external to the CIF.  This is a new and interesting idea that Howard has 
introduced and one that we should consider.  For the moment I wanted to 
clear up any misconception about the nature of _molecular_unit_atom_mu_id.

I apologize for spelling and typing errors as well as for my lack of 
knowledge of organic chemistry (I can do better in inorganic).  My 
ingorance in these fields matches Howard's in CIFology :-)

I hope, Howard, that you will be able to continue these discussions in 
Budapest.  I look forward to hearing how they turn out.  Sorry I will 
not be there.


Dr. I.D.Brown, Professor Emeritus,
Department of Physics and Astronomy
McMaster University, Hamilton
Ontario, Canada

coreCIFchem mailing list

[Send comment to list secretary]
[Reply to list (subscribers only)]