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Hi all..
I am trying to make large Pd(111) slab which conatins 5 layers and 2X2 cells for a large surface area. (3X3X1 KPOINTS)
Is it OK if I relax a 1X1 slab completely and then construct the slab by a small script or Do I need to relax the whole slab by making a initial 2X2 cell slab .. The calcualtion becomes notoriously big ..
Thanks in advance
Rajesh
PS: Does someone let me know a good source of VASP utilities scripts ...

I have found J. Li's atom eye utilities to be quite useful:
http://mt.seas.upenn.edu/Archive/Graphics/A/
There is a utility mul, under utilities, that multiplies a configuration file. You have to format the POSCAR file to .cfg format (he gives instructions on his website). I am under the impression that one must first converge the forces in the primitive cell to < 0.01 eV/ion and THEN multiply this configuration, after which running a subsequent calculation on the supercell until the forces converge to < 0.01 eV. There is a section in the VASP user's manual about this topic under "surface calculations" When you multiply your configuration, you will want to make sure that the (111) surface plane of your cell is exposed if this is the surface you want to study. You can achieve this by making a planar cut normal to the (111) surface using the mul utility available under the link I provided. Good Luck!