The ABINIT Users Mailing List ( CLOSED )

[Xavier Gonze <xavier.gonze@uclouvain.be>]

Try with iscf 7
Xavier

On 30 Jan 2008, at 03:12, P. Ganesh wrote:

> Dear All,
>
> While performing strutural optimization with "optcell 0" and  
> "ionmov 2", in the 23d broyden step, in the 6th iteration step  
> number I gett the following message:
>
> Min el dens= NaN         el/bohr^3 at reduced coord.  0.9833   
> 0.9815  0.9907
> ,Max el dens= NaN         el/bohr^3 at reduced coord.  0.0000   
> 0.0000  0.0000
>
> mkdenpos : WARNING -
>  Density went < 0 at    349920 points
>  and was set to  1.00E-14.  Lowest was  NaN      .
>  Likely due to too low boxcut or too low ecut for pseudopotential  
> core charge.
> ETOT  6 NaN                   NaN       8.268E-07 NaN        
> NaN       NaN
> scprqt: <Vxc>= -4.0855170E-05 hartree
>
> findmin : WARNING -
>  (scfcge) The second derivative is negative, equal to  
> NaN              .
> findmin : lambda_predict  NaN         etotal_predict  NaN
>
> scfcge: WARNING -
>  Potential-based CG line minimization has trouble to converge.
>  The algorithm is restarted with more secure parameters.
> scfcge: actual     6-2-1   6.8921E-01 NaN                 NaN
> scfcge: predict          NaN          restart the algorithm
> scfcge:
> scfcge: start      6-3-0   0.0000E+00 NaN                 NaN
>
>
> Loks like the line minimization is not converging.  I have tried  
> increasing the ecut by 30Ha and I get same problem.  Any  
> suggestions will be helpful.  My system is an insulator. I am using  
> v5.4.2.
>
> Thanks,
> Ganesh