Discussion List Archives

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

Report to IUCr Newsletter

Dear colleagues,

	I have enclosed below the draft of a report that I am planning to
submit to the IUCr Newsletter.  I am circulating this on the list for two
reasons, firstly to update members of Comcifs with the current status of
the dictionaries that are under development, and secondly to ask for any
corrections or updates.  If those of you who are working on dictionaries
would like to replace my description of your project with your own, please
send me the text you would like to see published.  Otherwise any
corrections or additions are welcome.  Please send them to my personal
address, idbrown@mcmaster.ca unless you want them posted on the Comcifs'
web discussion page.

			Best wishes

				David

*****************************************************
Dr.I.David Brown,  Professor Emeritus
Brockhouse Institute for Materials Research, 
McMaster University, Hamilton, Ontario, Canada
Tel: 1-(905)-525-9140 ext 24710
Fax: 1-(905)-521-2773
idbrown@mcmaster.ca
*****************************************************

Report from COMCIFS: New cif dictionaries.

     In the last report from COMCIFS published in the IUCr
newsletter (Vol.6 No.4 page 6) I described the current status of
the three approved dictionaries: the core, powder diffraction and
macromolecular dictionaries, and I gave details of the three
Dictionary Maintenance Groups that have been established to
continue their development.  

     However, there has been an increasing activity in developing
new dictionaries covering other specialised apsects of
crystallography.  Some of these dictionaries are nearing the
approval stage, others are just starting to work on defining the
essential concepts.  I give below a summary of the current state of
these dictionaries together with the name of the project leader. 
Anyone interested in contributing to any of these dictionaries
should contact the project leader.

MODULATED STRUCTURES (msCIF.dictionary)
Project leader: Gotzon Madariaga   wmpmameg@lg.ehu.es
     This dictionary will provide the necessary data items for a
complete description of modulated structures.  It is in an advanced
state of preparation and will shortly be presented to COMCIFS for
provisional approval.       

SYMMETRY (symCIF.dictionary)
Project leader: David Brown      idbrown@mcmaster.ca
     The purpose of this dictionary is to define all the symmetry
items that are needed to describe the contents of International
Tables vol A and to provide a framework in which, for example,
tables of sub- and super-groups can be can be expressed.  This
dictionary is still in the early stages of preparation.

DIFFUSE SCATTERING (dsCIF.dictionary)
Project leader: Thomas Proffen      proffen@pa.msu.edu
     The project group working on this dictionary are currently
identifying the concepts that need to be included in a diffuse
scattering dictionary.

ELECTRON DENSITY (rhoCIF.dictionary)
Project leader: Paul Mallinson      paul@chem.gla.ac.uk
     After a period of inactivity, work on this dictionary is
expected to restart in the next few months.  It will provide data
items that allow the results of electron density studies to be
reported.

SMALL ANGLE SCATTERING (sasCIF.dictionary)
Project leader: Marc Malfois        malfois@embl-hamburg.de
     A draft dictionary describing the items needed in the small
angle scattering field is under active development.

MAGNETIC STRUCTURES (magCIF.dictionary)
Project leader: Wieslawa Sikora     sikora@novell.ftj.agh.edu.pl
     This dictionary is being developed in conjunction with a
database of magnetic structures.  A draft dictionary is in the
course of active development.

IMAGE (imageNCIF.dictionary)
Project leader: Andy Hammersley      hammersl@esrf.fr
     This is not strictly a cif dictionary because it is designed
to report images in a binary format.  However, the non-image parts
of the file use cif-compatible names and a protocol has been
developed whereby the whole file, including the binary image, can
be converted to an ascii cif-compatible file.  This dictionary is
in an advanced state of development.

I.D.Brown
1998.11.30