I am trying to do slab calulations using 3 3 1 KPOINTS with PREC=MED which is taking longer time than we can afford.
Is it OK if i run 1 1 1 KPOINT calculation and then use the relaxed geometry for redoing the calculation using 3 3 1 KPOINTS.
Any suggestions or ways of handling this thing will be highly appreciated
thanx in advance
Slab calculations
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rajeshc
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Slab calculations
Last edited by rajeshc on Tue Aug 14, 2007 5:24 am, edited 1 time in total.
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admin
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Slab calculations
a Gamma-only calculation for a slab is rather risky (of course depending on the details of the electronic structure of your system). You can start some pre-convergence run with 1x1x1, but in any case you will have to check if the results (relaxed geometry) really corresponds to the equilibrium geometry by doing a few more ionic steps with an increased k-mesh.
another possibility to save computing time is to use soft PPs or to decrease the slab thickness (z). However, the vacuum size should be checked for convergence...
another possibility to save computing time is to use soft PPs or to decrease the slab thickness (z). However, the vacuum size should be checked for convergence...
Last edited by admin on Tue Aug 14, 2007 2:29 pm, edited 1 time in total.