Crystall Structure Relax

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sant · #1 Post by **sant** » Tue Mar 15, 2011 4:31 pm

Could you please let me know how to relax the lattice parameters , and coordinates obtained from the experimental value so that we can get new set of relaxed parameters and coordinates .

How to get it from VASP so that I again can build the structure with the relaxed unit cell.

Thank you.
S. Ant

boris · #2 Post by **boris** » Tue Mar 15, 2011 8:37 pm

Hi

use ISIF= 3.

And you can also read the manual, all should be explained

Boris

kambiz · #3 Post by **kambiz** » Tue Mar 15, 2011 11:33 pm

Dear S. Ant

you should use one of relaxation methods (not MD) with ISIF = 3, to relax ionic positions and the cell volume.

Kambiz

lexa · #4 Post by **lexa** » Wed Mar 16, 2011 9:53 am

And when you perform the run with ISIF=3 where do you get your lattice parameters from?? Are they the ones written in the CONTCAR??

Many thanks,
Lexa

kambiz · #5 Post by **kambiz** » Wed Mar 16, 2011 11:36 pm

I think you may read section 7.6. from VASP manual.

Kambiz

sant · #6 Post by **sant** » Thu Mar 17, 2011 7:36 pm

Thanks Kambiz ,lexa,Boris. My bulk is not cubic. OUTCAR gives lengths of vectors only ; no angles.
How to calculate the angles by using the lattice vector matrix shown in the CONTCAR file or OUTCAR.?

sant · #7 Post by **sant** » Thu Mar 17, 2011 8:20 pm

Since my str is monoclinic. What I am doing is taking the lattice vector matrix from CONTCAR and finding Eigen values. then Angle= cos^-1[a1.a2/norm of a1.norm of a2] Am I doing right or any other idea.?
Thank you,
S. Ant

jannypan · #8 Post by **jannypan** » Thu Mar 24, 2011 8:31 am

you can also read the manual, all should be explained WoW Gold Cheap
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