how to design a suppercell which contain a dislocation

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dyc_2008 · #1 Post by **dyc_2008** » Tue Mar 29, 2011 1:37 pm

dear all
how to design a suppercell which contain a dislocation？
it is easy to set the position of each atom to create a dislocation。but，there is a problem。
when the suppercell make up a grain periodically，the
extra-plane of atoms should be terminated at the edge of each suppercellâ€˜s boundary

thank you so much
<span class='smallblacktext'>[ Edited ]</span>

#2 Post by **admin** » Mon Apr 04, 2011 9:48 am

you are correct, the periodicity of the cells makes if difficult to define (large-range) dislocations. The only ansatz which can be chosen is to use large supercells

dyc_2008 · #3 Post by **dyc_2008** » Tue Apr 05, 2011 10:31 am

thanks

wjfriend · #4 Post by **wjfriend** » Fri Dec 07, 2012 12:53 am

Hi, I have the same problem now. Did you solve your problem?
What is the maximum number of atoms I can input in my supercell? Do we need to stop using the periodicity of the cell in VASP? How? Thanks.

magal · #5 Post by **magal** » Mon Dec 10, 2012 4:41 pm

Hi

Some time ago I found a thesis about modelling of Dislocations in Semiconductor Crystals using different methods (also DFT). Maybe it will be helpful to you.
You can find that thesis here:
http://144.173.231.195/research/qsystem ... thesis.pdf

Marta

wjfriend · #6 Post by **wjfriend** » Tue Dec 11, 2012 5:25 am

Thanks, Marta. I will take a look at the thesis.
Have you used VASP to solve this kind of problems?

magal · #7 Post by **magal** » Wed Dec 12, 2012 4:13 pm

Hi
No, I don't work with that kind of problems. I analyze defects such as impurity atom in the structure.

Marta