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How to correct the dipole's effect on planar averaged potential?

Posted: Thu Mar 19, 2009 7:58 pm
by sjtu
Hello,
My supercell is as below. the surfaces are A and B on two sides. So there is dipole across the system for the periodicity of the system. So the vassum level in the vacuum region is not flat. And now I am going to get the flat vaccum level on the B sides and the flat vacuum level on the A side.
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vac AAAABBBB vac
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There is one way I know can sovle the problem.
By setting the supercell like below:
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vac AAAABBBB vac BBBBAAAA vac
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But I want to use a small supercell to sovle the problem.
Is there anybody knowing how to set the INCAR to correct the potential?
Thank you so much.

How to correct the dipole's effect on planar averaged potential?

Posted: Fri Mar 20, 2009 3:44 pm
by admin
please set IDIPOL=3 (if the z-axis is pependicular to the slab) ; LDIPOL=.true. The dipole corrections will replace the slope of the potential in the vacuum (caused by the dipole moment across the slab by a {slightly smeared) step function in the middle of the vacuum, so the potential in the vacuum will be flat at each side of the slab (in a region sufficiently far away).

How to correct the dipole's effect on planar averaged potential?

Posted: Sat Mar 21, 2009 12:15 am
by sjtu
Thank you. I will try it.