[Pw_forum] about the from scale_h : error

[Lorenzo Paulatto]

On Wed, 03 Mar 2010 17:15:29 +0100, Wei Zhou <zdw2000 at gmail.com> wrote:
>      task #         0
>      from bfgs : error #         1
>      bfgs history already reset at previous step

I would say that "Pulay-stress" breaks the BFGS algorithm, what happens if  
you (manually) restart the calculation from the last valid configuration  
you've got? Also note that your atoms are so close now, that you are  
likely to get "diagonalization errors", in that case you'll need to find  
or generate harder pseudopotentials.


> it seems that the following OLD error come from     pot_extrapolation =
> 'second_order' ,
>     wfc_extrapolation = 'second_order' , I erase them then it disappear

Well, they were NOT specified in the input file you have sent to the list,  
furthermore it is specified in the documentation that those options should  
only be used for dynamics, not for BFGS.

best regards

-- 
Lorenzo Paulatto

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