Dear friends,
I want to relax the graphite which has hcp structure. I have constructed a unit cell of 72 atoms (3*3*4) and have employed GGA-91 pseudopotential. But, it seems that there is fluctuation in energy in ionic relaxation. Maybe, this kind of pseudopotential does not work. Please help, if any one has an idea.
Best,
Farzaneh
Relaxation of Graphite
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farzaneh
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Relaxation of Graphite
Last edited by farzaneh on Sun Dec 01, 2013 8:53 am, edited 1 time in total.
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admin
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Relaxation of Graphite
as the interlayer distance between the graphite layers is governed by van-der Waals interactions, a simple DFT calculation will most probably not converge (or give unreasonable results)
van-der Waals forces are implemented in vasp.5. only.
van-der Waals forces are implemented in vasp.5. only.
Last edited by admin on Mon Dec 02, 2013 3:42 pm, edited 1 time in total.
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farzaneh
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Relaxation of Graphite
Thank you for your comment. We have vasp 4.6. Can we update it? Do you know the update condition? Is it free?
Last edited by farzaneh on Mon Dec 02, 2013 6:33 pm, edited 1 time in total.