A new service starts at the SDPD mailing list, the UPPW :
             Unindexed Powder Pattern of the Week
 

Every week, a problem to solve will be proposed, you can
send solutions at uppw@cristal.org (provide the software
name, the cell, the M20 and F20 figures of merit and more if
you wish). These solutions, if any, will be summarized at the
SDPD mailing list the next week, while a new problem will be
offered. Anonymity will be ensured, unless the contrary is
specified.

If you possess an unindexed powder pattern and wish it to
be proposed as an UPPW, preferably send it to uppw@cristal.org
either as a list of d(A) (or 2-theta) and I values or as a digitized
pattern. Your problem will be queued ;-).

Best wishes,

Armel
 

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To: sdpd@yahoogroups.com
From: Robin Shirley <R.Shirley@surrey.ac.uk>
Date: Mon, 20 Oct 2003 15:42:13 GMT
Subject: Re: [sdpd] UPPW-1

Dear Armel

Your proposal is interesting, but is it intended primarily as a game or
as a service to science?  If the latter, then I think it would be more
realistic if other relevant data were provided, except of course where
there's really no further information.

What I have in mind, if available and applicable, is:

1) Sample preparation & purity, as far as is known
2) Radiation source (lab source? synchrotron? which one?)
3) Wavelength(s) used, if applicable
4) Instrument geometry used
5) Internal standard used, if any
6) Corrections applied, if any
7) And of course a profile would also be nice, if you have one

With best wishes

Robin Shirley
 
 
 

--------------------------------------------------------------------------------------
Date: Mon, 20 Oct 2003 23:40:18 +0200
From: Armel Le Bail <alb@cristal.org> (by way of Armel Le Bail <alb@cristal.org>)
Subject: Re: [sdpd] UPPW-1

>Your proposal is interesting, but is it intended primarily as a game or
>as a service to science?
 

Well, indexing is said to be an art. Most scientists ar so
enthusiastic with their job that they may feel playing a
game (sort of Trivial Pursuit). So it is difficult to answer
to your question. It is a game at the service of science.
 

The UPPW will hopefully suggest the most probable cells
lacking in many ICDD-JCPDS cards (nevertheless said
to be of high quality).
 

You can also consider that game as a mean to advertise
indexing software.
 

The fact is that during some recent congress, I heard some
people telling that they were searching for SDPD problems
to solve. Such problems are really numerous, the UPPW will
provide one problem per week, possibly breaking the indexing
bottleneck (though the most probable solutions are not
always the solutions ;-).
 

>If the latter, then I think it would be more
>realistic if other relevant data were provided, except of course where
>there's really no further information.
>
>What I have in mind, if available and applicable, is:
>
>1) Sample preparation & purity, as far as is known
>2) Radiation source (lab source? synchrotron? which one?)
>3) Wavelength(s) used, if applicable
>4) Instrument geometry used
>5) Internal standard used, if any
>6) Corrections applied, if any
>7) And of course a profile would also be nice, if you have one
 

Some of these informations are included inside of the
complete ICDD-JCPDS entries (see PDF-2). ICDD has not
considered useful to include the raw data somewhere,
unfortunately, but you may ask for the data to the author.

Nevertheless, indexing needs only the list of d(A) (and
intensities for some programs). The Grant-in-Aid origin
of the data means that ICDD has paid for obtaining them.
These data are supposed to be of the best quality that was
possible to attain on a conventional instrument.

Armel