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Hi,

I am doing NVT simulations. 32 molecules of water + Zinc atom, There is charge (+2) in the simulation box (L=9.96 Angstroms). Calculations are done at Gamma Point only. Please find my INCAR below. The energy drift is continuous and its about 0.2 eV/ps. Drift looks quite large.I am using the SCF optimized structure as my initial input. Rest of the parameters i.e Temperature, P.E & K.E with respect to time looks ok.

Any suggestions in this regard would be highly appreciated.

SYSTEM = Water with Zn
!
!---Startparameter_for_this_run---
PREC = Normal !Normal,Medium,High,Low,Accurate
ISPIN = 1 !Spin polarized calculation: 2-yes, 1-no
!
!---Electronic_Relaxation1---
ENCUT = 450
NELM = 100 !Maximum number of self consistent steps for the electronic loop
NELMIN = 4 !Minimumal number of self consistent steps for the electronic loop
NELMDL = -4 !nb_ELM_before_charge_update
EDIFF = 1.0E-05 !stopping-criterion_for_ELM [eV]
ALGO = Very FAST ! Normal
MAXMIX = 50
LREAL = A
LVDW= .TRUE.
!
!---Ionic relaxations---
NSW = 8000 !Maximum number of steps
IBRION = 0 !ionic relax:0-MD,1-DIIS,2-CG
LCORR = .TRUE.
ISIF = 2 !change_int_param:2-ion,3-volume,4-shape
!
!
NPAR = 4
IWAVPR = 11
NELECT = 266
MDALGO = 2
!---DOS_related_values---
ISMEAR = -1 !-5:tetrahedron,-1:fermi,0:Gaussian,N:Methfessel-Paxton(Metal)
SIGMA = 0.1 ! //0.1(with ISMEAR = 1) !smearing_width_ISMEAR
!
!---Write_flags---
LWAVE = F !write_WAVECAR
LCHARG = F !write_CHGCAR
LVTOT = F !write_LOCPOT,local_potential
LELF = F !write_electronic_localiz_function(ELF)
NWRITE = 0 !print the band energy only one ionic step
!---MD setting---
TEBEG = 350
TEEND = 350
!---Canonic (nose) MD
SMASS = 3
NBLOCK = 1
POTIM = 1.5

Request for your suggestions and comments on the INCAR.
Many Thanks in advance!

Thanking You,

Best Regards,
Anoop

<span class='smallblacktext'>[ Edited ]</span>

Dear all,

Any suggestions in this regard would be highly appreciated.
I tried with SMASS=0 also, It also shows quite similar drift.

Regards,
Anoop

The drift indicates that the system is not equilibrated properly. A liquid requires much longer simulation times not just 12 ps like you are doing. You can also increase the relative mass (via tuning SMASS) to slow down atomic motions.

many thanks for your suggestion.