I'm trying to relax a supercell with defect in the center (ISIF = 2) in respect to forces EDIFFG =-1.0E-3. The atoms of horizontal boundary of the cell have been fixed and are only allowed to move in the boundary plane.
This configuration does not converge. I can see that forces on the 'bulk' atoms vanish but the forces on the fixed boundary do not. Please help me understand this behaviour and how to fix it.
Constrained Force Relaxation
Moderators: Global Moderator, Moderator
-
- Newbie
- Posts: 2
- Joined: Wed Jul 17, 2013 11:25 am
- License Nr.: 5-442
Constrained Force Relaxation
Last edited by sonium on Wed Jul 17, 2013 3:02 pm, edited 1 time in total.
-
- Administrator
- Posts: 2921
- Joined: Tue Aug 03, 2004 8:18 am
- License Nr.: 458
Constrained Force Relaxation
atoms are not relaxed along the fixed directions, therefore the forces on them will not vanish for these components. they are not taken into account during the relaxation process and the check for convergence.
Last edited by admin on Thu Aug 29, 2013 11:37 am, edited 1 time in total.