As LHPM was derived from DBW2.9, it should be very similiar to
DBWS with respect to the input deck and
interface. We did have a visitor on
sabatical here recently who had been spoilt with GSAS and
did not appreciate having to hack into an ascii input deck.
During this time there were comments that in a semi
perfect world - "user friendly" menu based systems would allow Rietveld
users to concentrate on the science - rather than the computer
nasties of editing "cryptic" codewords - where errors are
not difficult to make. As the codewords in DBWS are directly below
the parameter fields, silly errors may be easier to spot - but in
LHPM - they are all in a bunch which can be intimidating to
new users.
In my opinion, any Rietveld package that cannot give an
immediate and convenient "interactive" Rietveld plot after
some cycles is at a real disadvantage compared to those that can.
This is definitely one area where many Reitveld packages,
(LHPM/RIET7 included) could be radically improved.
The recent post from Stanislaw Gierlotka about the shareware
DMPLOT program was thus very interesting.
-----------
The successor to LHPM is RIET7. This is not in a form
yet suitable for outside distribution - but has the
"superior" feature over other Rietveld packages that
it can handle VCT (variable count time) data - leading
to "better" and more stable structure refinement results
for potentially thorny problems.
This is described in :-
(Madsen, I.C. and Hill, R.J., (1992), Adv. X-ray Anal.
35, 39-47) and a sequel is in press.
For those interested in seeing some sample data and
Rietveld plots, anon ftp to :-
sol.dmp.csiro.au:/pub/xtallography/vct. Sample raw data
and Rietvelld plots are given in ascii, HPGL and Postscript
format.
Lachlan.
------
Lachlan Cranswick - CSIRO _--_|\ lachlan@dmp.CSIRO.AU
Division of Mineral Products / \ tel +61 3 647 0367
PO Box 124, Port Melbourne \_.--._/ fax +61 3 646 3223
3207 AUSTRALIA v