Random atomic positions in crystal lattice

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Yesheng
Posts: 11
Joined: Mon Sep 03, 2012 10:09 pm

Random atomic positions in crystal lattice

Post by Yesheng » Thu Nov 29, 2012 11:40 pm

Hi all,

I have a compound with four elements, let's call them A, B, C and D, I'm interested in making elements A and B disordered in the lattice, and elements C and D ordered. This just means that elements C and D always occupy the same coordinates, while the coordinates of A and B can be randomized in the compound. I found an input variable 'random_atpos' that can potentially be used for this purpose, but does anyone know if it's possible to have just elements A and B disordered, while keeping C and D on ordered lattice coordinates?

Thanks a lot.

Boris
Posts: 128
Joined: Tue Feb 16, 2010 10:13 am
Location: France

Re: Random atomic positions in crystal lattice

Post by Boris » Tue Dec 04, 2012 9:59 am

Hi

I don't know if abinit can do that. Alternatively, you can use a special quasi random structure (SQS) as input structure for abinit. The SQS will be a small supercell that will mimic as closely as possible the random distribution of your A and B elements. You can use ATAT (http://www.its.caltech.edu/~avdw/atat/) to build the SQS (see the manual). It usually works well for modelling alloys.

Good luck

Boris
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Boris Dorado
Atomic Energy Commission
France
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Yesheng
Posts: 11
Joined: Mon Sep 03, 2012 10:09 pm

Re: Random atomic positions in crystal lattice

Post by Yesheng » Thu Dec 06, 2012 12:05 am

Ok thank you very much for your help Boris.

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