Large Energy Drift in Long Running Molecular Dynamics
Posted: Wed Jun 01, 2011 7:16 pm
I am trying to run a long running 100 ps + MD using VASP.
It is a MgO supercell with 64 atoms
I have read the discussions about this issue in Q&A.
Following the instructions, I have set
EDIFF=1e-7
LREAL = .F.
POTIM = 0.5
HOWEVER, the problem is still there!
The initial energy is
-.42049186E+03
and eventually it reaches
-.41990760E+03
after 80000 steps.
The temperature of the system increases from ~100K to ~140K accordingly.
I am wondering if anyone can help me solve this problem.
Many thanks.
The INCAR file is attached for your reference.
SYSTEM = MgO - MD
Start parameter for this Run:
NWRITE = 0
ISTART = 1 job : 0-new 1-cont from WAVECAR 2-samecut
ICHARG = 0 0-from ini-wf 1-read CHGCAR 2-superposition of ACD
INIWAV = 1 0-lowest 1-random
ISPIN = 1
# MAGMOM = 23*1 23*-1 -1 1
ISYM = 0 0-nonsym 1-usesym
PREC = medium
# IDIPOL = 4
# GGA = 91
# VOSKOWN = 1 0-usual 1-magnetic
Writing Files
LCHARG = F
LWAVE = F
Electronic Relaxation
# ENCUT = 350
EDIFF = 1E-07 stopping-criterion for ELM
LREAL = .F. Auto
NELMIN = 4
Ionic Relaxation and MD
# ISIF = 7
# SMASS = -1
NSW = 80000
NBLOCK = 1
# KBLOCK = 1
IBRION = 0 -1-fixed 0-MD 1-quasi-New 2-CG 3-DMD
TEBEG = 100 start temperature
TEEND = 100 final temperature
# EDIFFG = -0.01 stopping-criterion for IOM
POTIM = 0.5
# NBANDS = 256
DOS related values:
ISMEAR = 0
SIGMA = 0.05
# EMIN = -7
# EMAX = 3
# RWIGS = 1.029 0.769
# LORBIT = 11
Algorithm:
IALGO = 48
# NPAR = 1
<span class='smallblacktext'>[ Edited ]</span>
It is a MgO supercell with 64 atoms
I have read the discussions about this issue in Q&A.
Following the instructions, I have set
EDIFF=1e-7
LREAL = .F.
POTIM = 0.5
HOWEVER, the problem is still there!
The initial energy is
-.42049186E+03
and eventually it reaches
-.41990760E+03
after 80000 steps.
The temperature of the system increases from ~100K to ~140K accordingly.
I am wondering if anyone can help me solve this problem.
Many thanks.
The INCAR file is attached for your reference.
SYSTEM = MgO - MD
Start parameter for this Run:
NWRITE = 0
ISTART = 1 job : 0-new 1-cont from WAVECAR 2-samecut
ICHARG = 0 0-from ini-wf 1-read CHGCAR 2-superposition of ACD
INIWAV = 1 0-lowest 1-random
ISPIN = 1
# MAGMOM = 23*1 23*-1 -1 1
ISYM = 0 0-nonsym 1-usesym
PREC = medium
# IDIPOL = 4
# GGA = 91
# VOSKOWN = 1 0-usual 1-magnetic
Writing Files
LCHARG = F
LWAVE = F
Electronic Relaxation
# ENCUT = 350
EDIFF = 1E-07 stopping-criterion for ELM
LREAL = .F. Auto
NELMIN = 4
Ionic Relaxation and MD
# ISIF = 7
# SMASS = -1
NSW = 80000
NBLOCK = 1
# KBLOCK = 1
IBRION = 0 -1-fixed 0-MD 1-quasi-New 2-CG 3-DMD
TEBEG = 100 start temperature
TEEND = 100 final temperature
# EDIFFG = -0.01 stopping-criterion for IOM
POTIM = 0.5
# NBANDS = 256
DOS related values:
ISMEAR = 0
SIGMA = 0.05
# EMIN = -7
# EMAX = 3
# RWIGS = 1.029 0.769
# LORBIT = 11
Algorithm:
IALGO = 48
# NPAR = 1
<span class='smallblacktext'>[ Edited ]</span>