Dear Folks,
I am calculating a system using GGA+U method. However, I found the first several ionic steps never converge during the electronic loops, even when I increase the NELM to a larger number (>40).
This seems not a big problem for geometry optimization, but a hurdle when someone need to calculate the DOS, where only one ionic step is needed.
Could someone tell me what can I do?
Thanks,
Burns
GGA+U's convergence
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Burns
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GGA+U's convergence
Last edited by Burns on Tue Jun 08, 2010 12:49 am, edited 1 time in total.
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boris
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GGA+U's convergence
Hi
The electronic steps should converge at last. When it does, restart the calculation with only one ionic steps and use the previous charge density file (istart = 0, icharg=1)
It should work.
The electronic steps should converge at last. When it does, restart the calculation with only one ionic steps and use the previous charge density file (istart = 0, icharg=1)
It should work.
Last edited by boris on Tue Jun 22, 2010 9:12 am, edited 1 time in total.
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ngold
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GGA+U's convergence
I'm not sure if this is still an issue, but I wonder to what value you've set your smearing. Setting it to something too low will frequently result in convergence issues for metallic systems.
Last edited by ngold on Thu Feb 17, 2011 11:26 pm, edited 1 time in total.