[Pw_forum] minimization in CP molecular dynamics

[Nicola Marzari]

Mansoureh Pashangpour wrote:
> dear Nicola
> this is ekinc for end of minimization I found it small after verlet dynamics
>  ekinc         :        0.10064       0.10064 (AU)
>  ekin          :      144.72166     144.72166 (AU)
>    epot          :     -473.07863    -473.07863 (AU)
>    totel energy  :     -280.01088    -280.01088 (AU)
>  
> why they are different with
>  > scf:  total energy              =  -243.33284101 Ry


It is actually (very) large, and it needs to be well below 10-5 au.

If after that it's still different, try something easy - a hydrogen
molecule, and go from there.

In any case, the fact that the cp calculation has a much lower energy
than pwscf means that probably something incorrect is going on. As
mentioned, try very simple things, and move up from there.


				nicola

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