[Pw_forum] file not converging

[Ngoc Linh Nguyen]

kajal jindal wrote:
> I am working on a 3*3*3 supercell of ZnO...and I am doping Co into 
> it... but when I am doing the scf calculations, the file does not 
> converge..... The scf Accuracy keeps on oscillating and finally 
> displays the message "100 iterations completed, file does not 
> converge".... I have read forum regarding this problem.. and have 
> accordingly increased the  value of degauss to 0.05...ecutwfc to 30 
> Ry....ecutrho to 400 Ry....
> I have kept mixing_ beta=0.1... amd mixing_mode = local-TF....My 
> structure has 969 electrons and accordingly I have kept the value of 
> nbnd=600... 
The problem of non-convergence could be resulted by the atoms' 
configuration, so in opinion,  
   - you should check again Co doping into ZnO substrate if it has any 
problem such as overlap position or too close between atoms. Normally, 
with that problem you should enclose the input file when you make a 
question, it could help members clear to find out the reason. 
 Moreover, you can increase degauss to lager values such as 0.07 ; 0.1; 
0.3 and check if the calculation is converged or not.

Good luck

Linh



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