[QE-users] problem in relaxtion

[Gui Wei]

Hi,

     When optimizing the Fe（110）surface( two layers,a total of 60 atoms,the bottom layer is fixed),I found that it can not converged.I added a command:nbnd=380(the number of electrons is 480),and get a strange result:

     Total force = 0.001442     Total SCF correction = 0.000399
     SCF correction compared to forces is large: reduce conv_thr to get better values
     BFGS Geometry Optimization
     bfgs converged in   1 scf cycles and   0 bfgs steps
     (criteria: energy <  1.0E-03 Ry, force <  1.0E-02 Ry/Bohr
     End of BFGS Geometry Optimization
     Final energy   =   -8502.2661470662 Ry
     The calculation only make one scf cycle and the atomic coordinates have barely changed.My purpose is to optimize and get that energy to calculate the binding energy,but this value is inaccurate.Could someone give me some advice?

Gui Wei
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20180907/c0301647/attachment.html>