[Wien] How to select proper K-mesh for slab

[Donghui Guo]

Dear all WIen2k users,

I am not clear how to select proper k-mesh for slab, even after I searched in mailing list.
For bulk strutcture, I used (10x10x10) k-mesh, and then I made slab by "x supercell". So far, the slab is (1x1x10) with 20 bohrs vacuum. Should I use k-mesh of (10x10x1)?  In another word, if x and y directions are not multipled in real space, should the k-mesh keep the bulk parameter in x and y directions？ 
Meanwhile, I found a email (posted by Mr. Andersen at Jun 1, 2004) which said "usually a k-mesh with (X X 1), where X is any odd number, is considered good for a surface". I don't know why "odd number" is "good for surface".
Thank you in advance.

Best regards, 
Yours, 
Donghui Guo
2009-03-16


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Donghui Guo 
Catalysis Research Center (CRC)
Hokkaido University
21-10 Kita, Sapporo 001-0021
Japan
dhguo at cat.hokudai.ac.jp
TEL: +81-11-706 9114 (office)
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