Nudged Elastic Band Set up with B3LYP
Posted: Tue Feb 21, 2017 2:45 pm
I have a 19-atom molecule (C,H,O only) in an 18 Angstrom cubic box and I'm trying to set up an NEB calculation. I did the following:
1) Relaxed the initial and final structures and called them POSCAR00 and POSCAR03
2) Made a parent directory containing the following files: KPOINTS, INCAR, POTCAR, POSCAR00, POSCAR03, and the vasp.sh script
3) Used the nebmake.pl script to generate 2 images so that I now have a POSCAR file in all of the following subdirectories: 00,01,02,03
My INCAR file for the NEB run with the B3LYP functional is:
SYSTEM = 2ACP
ISMEAR = 0 ! Gaussian smearing
NSW = 500 ! 500 ionic steps
LCLIMB = .TRUE.
LSCALAPACK= .FALSE.
IMAGES=2
SPRING = -5
ICHAIN=0
IBRION = 2 ! use the conjugate gradient algorithm
POTIM = 0.5
LHFCALC = .TRUE.
GGA = B3
AEXX = 0.2
AGGAX = 0.72
AGGAC = 0.81
ALDAC = 0.19
EDIFFG = -0.05
I'm wondering if this is set up correctly or if I am missing anything.
I've read that IBRION=2 usually fails to converge but it seems to be converging. I wasn't sure if I chose POTIM correctly or if it is necessary to include LSCALAPACK= .FALSE.
Thank you!
1) Relaxed the initial and final structures and called them POSCAR00 and POSCAR03
2) Made a parent directory containing the following files: KPOINTS, INCAR, POTCAR, POSCAR00, POSCAR03, and the vasp.sh script
3) Used the nebmake.pl script to generate 2 images so that I now have a POSCAR file in all of the following subdirectories: 00,01,02,03
My INCAR file for the NEB run with the B3LYP functional is:
SYSTEM = 2ACP
ISMEAR = 0 ! Gaussian smearing
NSW = 500 ! 500 ionic steps
LCLIMB = .TRUE.
LSCALAPACK= .FALSE.
IMAGES=2
SPRING = -5
ICHAIN=0
IBRION = 2 ! use the conjugate gradient algorithm
POTIM = 0.5
LHFCALC = .TRUE.
GGA = B3
AEXX = 0.2
AGGAX = 0.72
AGGAC = 0.81
ALDAC = 0.19
EDIFFG = -0.05
I'm wondering if this is set up correctly or if I am missing anything.
I've read that IBRION=2 usually fails to converge but it seems to be converging. I wasn't sure if I chose POTIM correctly or if it is necessary to include LSCALAPACK= .FALSE.
Thank you!