to my point of view it actually IS important to have as much info
available as possible. Why not JCPDS-card with R-marks?
Also more computing seems to be possible, as was stated, when
instrument-independent data were claimed.
B U T - remember: NOT every JCPDS-user is familiar with crystallography.
We all know how to use our tools and each of us has found a way to deal
with lots of different data-formats. The following will give you an
insight, what problems we have to face right here in our place to come to
a refinement of a single pattern:
A friend in the neighbouring group prepared a diffraction pattern on a
Siemens diffractometer.
First problem: The data is collected on a PC (not linked to Internet), but
the program is on a unix-machine in the net. Data conversion from RAW to
an ascii format is recommended.
Siemens' routine does not work correctly (who knows why). Solution:
Employ DRX-Win (which is commercial and only the commercial version will
read/write ascii-data). But also here, you have to face a bug: XY-format
in columns is made, but x is always INTEGER (therefore, with a resolution
of .02 2Q, you will have 50 lines reading like this:
10 625
10 631 etc.
Solution: Use EXCEL (which you have to call with american number format
setting, because the unix machine will read the german floating number
10,02 as two numbers) to calculate the 2Qs correctly, save as text file.
Now: transfer to the host - no problem.
Another conversion is recommended into the format my Rietveld program reads
(actually I use FullProf, MINREF or SIMREF, which have three different
input-files and three different data-formats).
After ca. 2 h work, the data have arrived where they can be used and in
format I'd like them to be !!
A "standard computer user" in our group (we are all chemists) would have
given up at problem no 2 or 3. Guess, what time it had cost, when I did
this for the first time in my life! Now I'm doing this in routine operation.
The point of all this is: Don't think egoistic with this computer stuff!
I think JCPDS is a successful concept, because it is easy for everyone to
access the data. Don't make access too complicated, or all the people who
are not interested in long problem-solving sessions on the computer may not
buy it any more.
By the way, a point that really makes me mad is: Why are the Rietveld
codes free shareware when you have to do a thousands of tricks to get the
ready-fitted profile visible? E.g. FullProf (to my knowledge) does not
support any ascii-plot format. The only tool I know to plot FullProf's
results is DRX-Win, which you can buy for some 400 $.
Wow - this is a long message! I'll have to be off for lunch with the group.
I wait for answers.
Greetings
Carsten