The ABINIT Users Mailing List ( CLOSED )

["D. R. Hamann" <drhamann@mat-simresearch.com>]

Matthieu Verstraete wrote:
> Is NiAl spin polarized?
>
> > Therefore I decided to determine the elastic constants by calculation 
> > of the
> > energies of strained samples.
> Don Hamann has told us several times there is quite a large error on 
> the end result. Using finite differences of stress tensors should be 
> better (correct?).
This is correct.  However, the most accurate results should be gotten 
using the response-function methods as for Al in the tutorial.  Why the 
program aborted when you tried this is probably a compiler issue, since 
the test suite does test this kind of calculation.  See if you can run 
tests/v4/test 79 successfully, which does elastic constant calculations 
for spin-polarized Fe.
If you can't you are probably dealing with a compiler bug.

I'll repeat other's comments that you do need to do convergence testing 
in both ecut and the k sample.  Ni is very demanding (test 79 is nowhere 
near converged).

Don Hamann

--
D. R. Hamann
Mat-Sim Research LLC    | Deptartment of Physics
P.O. Box 742            |  and Astronomy
Murray Hill, NJ 07974   | Rutgers University
phone: 908-370-8079     | 732-445-4381

email: drhamann@mat-simresearch.com