[Pw_forum] Restart calculation of LSDA

[hanghui chen]

Dear PWSCF users,
      I have a question of how to efficiently restart the calculation of
LSDA. It is a little bit complicated.
      The system I study is always metallic.
      When I relax a system using LDA, usually I can first relax it at a
'high temperature' (a wider broading width for smearing) and a coarse k
grid. Then I use the relaxed atomic positions and the charge density
(charge-density.dat) to restart the relaxation at a 'lower temperature' and
a more dense k grid.
      However if I run a spin-polarized calculation (LSDA), I find that a
system could be paramagnetic at "high temperature" and ferromagnetic at 'low
temperature'. However if I relax a big system using very small broading
width and a very dense k grid, it is too computationally intensive. But if
I first relax it using a wider broading width and a coarse k grid, the
system will relax to a paramagnetic state. Then if I restart it, the
system will always be in the paramagnetic state.
      So is there a clear trick so that I can restart the calculation using
the previous charge density but make a new initial guess for the
magnetization rather than reading from the file "spin-polarization.dat'?
      Thank you very much.

Hanghui Chen
Department of Physics
Yale University
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20090227/544a5984/attachment.html>