relaxiation of the lattice
Posted: Fri Sep 17, 2010 12:57 pm
how would I relax the lattice structure in x and y direction and keep the strain in z direction?
Thank you.
Thank you.
Hi,
Take your initial structure and compute the stress tensor acting on it, but without relaxing any lattice parameters (use e.g. ISIF=2). Subsequently, retrieve the stresses in x and y-direction from your OUTCAR.
Then, construct a new POSCAR with the c-lattice parameter as before but with a and b scaled according to a certain scalar value. You need to adapt a and b according to the stresses computed in the previous step, e.g. make the lattice vector b bit smaller if you found compressive stresses in the y-direction.
Iterate until you have reached a certain desired accuracy. I believe people have posted bash scripts on this forum before that automate this procedure.
<span class='smallblacktext'>[ Edited Fri Sep 17 2010, 06:42PM ]</span>