[Pw_forum] question on electron_dynamics and orthogonalization

Nichols A. Romero naromero at gmail.com
Thu Mar 30 00:41:11 CEST 2006


Nicola,

I notice that when I compile the code in serial mode (i.e. removed
both -D__MPI and -D__PARA) and then run the same calculation I get a
stress tensor of zero. I'm attaching my output. The forces and
energies do not change.

On 3/29/06, Nicola Marzari <marzari at mit.edu> wrote:
>
> Thanks.
>
> > I will play with it a bit more to see if I can isolate the problem. I
> > do recall that the stress changes on the order of 0.5 GPa per
> > component when I changed either
> > emass_cutoff
> > or
> > nr1b,nr2b,nr3b
> >
>
> The only reason while it would change with emass_cutoff is that
> you are not perfectly converged (I think). With enough iterations,
> emass_cutoff shouldn't matter; it is just a preconditioning to take
> into account that the hamiltonian is diagonally dominanant, in a plane
> wave basis set, with the diagonal diverging as G^2.
>
> nr1b... etc: well, let's revisit this as soon as CP is fixed. Paolo
> and Carlo have been kindly working on this.
>
>                         nicola
>
>
> ---------------------------------------------------------------------
> Prof Nicola Marzari   Department of Materials Science and Engineering
> 13-5066   MIT   77 Massachusetts Avenue   Cambridge MA 02139-4307 USA
> tel 617.4522758 fax 2586534 marzari at mit.edu http://quasiamore.mit.edu
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>


--
Nichols A. Romero, Ph.D.
1613 Denise Dr. Apt. D
Forest Hill, MD 21050
443-567-8328 (C)
410-306-0709 (O)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: nitromethane.cp.out.serial
Type: application/octet-stream
Size: 22456 bytes
Desc: not available
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20060329/7824e453/attachment.obj>


More information about the users mailing list