test criteria for vacuum region for surface calculation

Queries about input and output files, running specific calculations, etc.


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engr1
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test criteria for vacuum region for surface calculation

#1 Post by engr1 » Tue Feb 22, 2011 9:58 am

Hello!
I want to make surface relaxation calculation for Ge with suitable vacuum slab. Is there any criteria to set this vacuum slab w.r.t bulk layers. Or is there any check to test whether vacuum slabe is reasonable. Does the length of vacuum slab have any effect on dipole correction energy if IDIPOL is set to 3?
Last edited by engr1 on Tue Feb 22, 2011 9:58 am, edited 1 time in total.

apple
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test criteria for vacuum region for surface calculation

#2 Post by apple » Wed Feb 23, 2011 5:03 am

To establish the right vacuum size, run several calculations for structures with different vacuum size keeping the number of bulk layers the same. Compare their energies. You will see that at some point, increasing the vacuum even further does not make any difference in the total energy.
Last edited by apple on Wed Feb 23, 2011 5:03 am, edited 1 time in total.

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