Hello, everyone!
I am doint calculations of large systems (surfaces and bulk) with number of atoms from 40 - 200. I set LREAL=.TRUE. flag. Electronic convergence is not a problem, ionic is. When I put EDIFFG=-0.1, everything is OK, but when I increase this criteria up to -0.01 I see a drift forces. I use PREC=Normal, ENCUT=1.3*ENCUT, ADDGRID=.TRUE. parameters. Any idea how to improve ionic convergence?
P.S. I found on VASPtips, that including LREAL flag brings less accuracy and a large drift on forces, so it was suggested against this flag. So, is it really important to use this flag?
LREAL flag
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proffess
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LREAL flag
Last edited by proffess on Tue Nov 07, 2006 11:05 pm, edited 1 time in total.
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admin
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LREAL flag
if the drift of forces is substantial,
1) please set PREC=high.
2) if you calculate a slab or cluster, please keep the position of at least one layer (atom) fixed in space, using the Selective Dynamics tag
1) please set PREC=high.
2) if you calculate a slab or cluster, please keep the position of at least one layer (atom) fixed in space, using the Selective Dynamics tag
Last edited by admin on Tue Nov 14, 2006 2:54 pm, edited 1 time in total.