[Pw_forum] Is the "cell_dofree" functionality fully implemented in Espresso 4.0.x?

[Lorenzo Paulatto]

Serge Nakhmanson ha scritto:
> Dear All,
>
> Is "cell_dofree" feature in &CELL completely implemented
> in Espresso 4.0.x?
Dear Serge,
I can't give you a definitive answer, as I haven't really used this
feature. What I can say is that it is not implemented with bfgs
algorithm and even with damp I'm not really sure it is working. I tried
to find a quick fix some time ago, but had to give up due to other work.

> condition in vcsmd.f90 is never reached. Or am I missing
> something?
>   
I think you are right, but it is easy to fix, change
  ABS( sigma(i,j) ) * uakbar
to
  ABS( sigma(i,j) ) * iforceh(i,j) * uakbar
in both places (be careful with the indexes), and it *should* work.

I say "should" because I have done a few tries, but couldn't make it
converge; it is probably due to my inexperience with damped dynamics.

> Would appreciate any sage comments on this.
>   
I''m not really a sage, I hope it helped

bye

-- 
Lorenzo Paulatto
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