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dear friends

I want to carry out simulated annealing for geometry optimization of an oxide. I want to heating up to 1500K from 1030k in 10000 steps. My INCAR file was set as follows:

ENCUT = 450 eV
EDIFFG = 0
EDIFF = 1E-7

NSW = 10000
IBRION = 0
POTIM = 2.0
SMASS = 2
TEBEG = 1030
TEEND = 1500

NPACO = 200
APACO = 20.0

IALGO = 8
LREAL = .TRUE.

NBLOCK = 1
KBLOCK = 200

ISTART = 1
ICHARG = 1

the following is my OSZICAR:
1 T= 1018. E= -.52866716E+02 F= -.53656031E+02 E0= -.53650722E+02 EK= 0.78932E+00 SP= 0.00E+00 SK= 0.27E-07
2 T= 992. E= -.52866644E+02 F= -.53635723E+02 E0= -.53630124E+02 EK= 0.76910E+00 SP= -.18E-04 SK= 0.72E-06
3 T= 961. E= -.52865170E+02 F= -.53610487E+02 E0= -.53604542E+02 EK= 0.74541E+00 SP= -.94E-04 SK= 0.53E-05
4 T= 928. E= -.52865522E+02 F= -.53584687E+02 E0= -.53578383E+02 EK= 0.71942E+00 SP= -.27E-03 SK= 0.21E-04
5 T= 893. E= -.52866168E+02 F= -.53558237E+02 E0= -.53551610E+02 EK= 0.69261E+00 SP= -.60E-03 SK= 0.61E-04

i have two question:
The parameters in my INCAR are right or wrong?
Why the temperature "T" in OSZICAR decrease rather than increase?

The simulation is not coupled to the heat bath at every step, so it may drift down at the beginning if it was not equilibrated to 1030 K (e.g. starting from a 0K structure). The coupling frequencey is determined by your SMASS paramater: http://cms.mpi.univie.ac.at/vasp/guide/node118.html

One more thing: EDIFF = 1E-7 is incredibly high convergence for an MD calculation. Even for a small system, it would take a very long time to reach 10000 steps.

Thanks very much.
Could you please suggest me what changes I should make in the INCAR file so that I can achieve my desired annealing? How long does it take to heat the system from 1030 to 1500?