[Wien] BFGS minimization

[L. D. Marks]

I have coded a somewhat more robust BFGS miminizer from the
PORT library (http://www-out.bell-labs.com/project/PORT/)
into WIEN2K. It seems to work fine, and if anyone wants to
test it (I have limited computer resources) contact me
directly. It is currently implimented using the energy
and forces (-fc), but I wonder if that is the right approach
to use in all cases, particularly if approximations (for
speed) are made with RKMAX/k-points etc. I'd be interested in
comments (since I have limited experience) about how useful
minimization on ||Force||, either full or just the HF forces
might be, particularly if these converge faster with approximate
RKMAX than the energy.

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Laurence Marks
Department of Materials Science and Engineering
MSE Rm 2036 Cook Hall
2225 N Campus Drive
Northwestern University
Evanston, IL 60201, USA
Tel: (847) 491-3996 Fax: (847) 491-7820
mailto:ldm at risc4.numis.northwestern.edu
http://www.numis.northwestern.edu
Nanocrystallography Workshop, http://ncem.lbl.gov/workshop.htm
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