Geometry Optimization

[atk_user]

Dear all,

I am try to calculate the Al unit cell with OptimizeGeometry.
However, the geometry is not changed... (Lattice parameters)
I did not consider Constrain cell and Optimizer Method is QuasiNewton, PBE functional, and DZP basis sets.

I don't know what's the problem. Could you help me?

 

[Umberto Martinez]

can you provide your python input script?

[atk_user]

Here's the input file you asked me to send you.

Thank you for your help.

[Umberto Martinez]

There is nothing wrong with your calculations, the job finished because it reached all the convergence criteria you set. In particular the maximum stress criteria of 0.01 eV/Å**3. You can check it if you include the Stress analysis in the calculation:

Code

+------------------------------------------------------------------------------+
| Stress Report                                                                |
+------------------------------------------------------------------------------+
| [[  9.05881942e-03   5.25907270e-31   7.88860905e-31]                        |
|  [  7.89246091e-31   9.05881942e-03   5.25907270e-31]                        |
|  [  5.26356654e-31   6.57319890e-31   9.05881942e-03]] eV/Ang**3             |
+------------------------------------------------------------------------------+

You should use a much lower value, something like 0.001 eV/Å**3. See for example here this section: http://quantumwise.com/publications/tutorials/mini-tutorials/244#h3-setting-up-the-bulk-configurations

[atk_user]

Thank you Martinez. I'll try with your suggestion.
Thank you for your help again. 

Have a good day.