[sdpd] Re: [ PowBase]

[John Faber <faber... @icdd.com>]

At 04:50 PM 11/8/99 +0100, you wrote:
> Andrew S. Wills wrote :
>
> >Armel, how would you feel about accepting magnetic data? -are you accepting
> >all waifs and strays (sdf's in French)? :-) Or perhaps Alan, you would 
> prefer
> >to house them at the ILL.
>
> I think that sounding opinions about doing or not a database, and
> asking to researchers if they are ready to share their data would
> have surprising results (large percentage of "no", very probably).
>
> So, the question is, will the base increase ? The ICDD base receives
> data from ICDD members, grants in aid, essentially (?), and the
> failure of this method to provide a complete database is evident
> with the recent add of calculated patterns from ICSD and in a
> near future from CSD.

Armel:

The Facts:
The Grant-in-Aid (GiA) Program at ICDD is currently supported at about 
$300,000 per year.
The  GiA program is not restricted to ICDD members.
The published aim of the program is to promote PDF-2 data.  We ask for PDF-3.
The ICDD does not receive free patterns from the ICSD or the CSD; this is 
covered by a contractual arrangements between these entities.

John

> The size of PowBase for 80 patterns is 800Ko, thanks to compression
> by Winzip. A base of 3000 patterns would be 30Mo, and this is
> not a problem, even on a simple PC with full Internet connection. The
> same PC stores already a base of more than 10000 most cited chemists
> (ISI data). But clearly, ToF large data should be left at ISIS or elsewhere.
> And a base of magnetic data would be self consistent at ILL. How to
> manage a very simple database is explained at the PowBase Web site.
> But who wants to manage a free database apart me ?-)). Or who
> has permission to do it ? Is that possible at NIST ? Ask yourself why
> such databases are so few. The Studsvisk database of amorphous
> diffraction patterns (powder-like) is still underdeveloped (because
> nobody sends data ?).
>
> Now let us discuss about standard formats. Why CIF has to be
> so complex ? The aim is to produce a completely self consistent
> block of data which would allow to do not need the corresponding
> publication at all. In fact, IUCr can almost produce automatically
> a standard publication from a CIF file. And the atomic coordinates are
> supposed to be included, of course. But if one considers that the
> publication will be available separately, then the format has certainly
> not to be so complete, and only the point by point intensities are
> really needed (for a constant wavelength powder pattern). May be
> you heard about PubMedCentral or E-Biomed, a free access project
> for  electronic publications at NIH. It is a pity that the project was not
> more general, because a big PubCentral would solve that problem : no
> need for a so complete and complex CIF when publications are available
> online (and for free...).
>
> I would have one question about PDF-3. Up to now, ICDD never
> produced atomic coordinates. And I guess that the World has been
> commercially divided in databases with or without atomic
> coordinates. So the question is, will the CIF star include atomic
> coordinates inside PDF-3 ? If not, either the publication or another
> database (ICSD, CSD) will be needed, eventually, if more than
> an identification of a compound is the target.
>
> Best,
>
> Armel Le Bail
> http://www.cristal.org/powbase/
>
> Armel Le Bail - Universite du Maine, Laboratoire des Fluorures,
> CNRS ESA 6010, Av. O. Messiaen, 72085 Le Mans Cedex 9, France
> http://www.cristal.org/
__________________________________
Dr. John Faber
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