Large Energy Drift in Long Running Molecular Dynamics

Queries about input and output files, running specific calculations, etc.


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abalone
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Large Energy Drift in Long Running Molecular Dynamics

#1 Post by abalone » 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>
Last edited by abalone on Wed Jun 01, 2011 7:16 pm, edited 1 time in total.

support_vasp
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Re: Large Energy Drift in Long Running Molecular Dynamics

#2 Post by support_vasp » Thu Sep 12, 2024 8:52 am

Hi,

We're sorry that we didn’t answer your question. This does not live up to the quality of support that we aim to provide. The team has since expanded. If we can still help with your problem, please ask again in a new post, linking to this one, and we will answer as quickly as possible.

Best wishes,

VASP


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