Question about NVE MD

[mongon]

Dear all users,

It's the first time I'm doing the NVE MD via VASP.

I set the TEBEG = 400 in the INCAR file. However, after thousand even several hundreds time steps, the temperature drops dramatically to 200 K. Is is normal? Why it will drop?

Here is my INCAR file and parts of the OSZICAR file.
SYSTEM= Test
PREC = Low
ENCUT = 150
IALGO = 38
ISMEAR = 1
SIGMA = 0.3
LREAL = Auto
IBRION = 0
NSW = 5000
ISYM = 0
SMASS = -3
POTIM = 1.00
TEBEG = 400
EDIFF = 2e-5
ISIF = 2

1 T= 400. E= -.15997238E+03 F= -.16653867E+03 E0= -.16650214E+03 EK= 0.65663E+01 S
P= 0.00E+00 SK= 0.00E+00
2 T= 400. E= -.15997244E+03 F= -.16653683E+03 E0= -.16650031E+03 EK= 0.65644E+01 S
P= 0.00E+00 SK= 0.00E+00
3 T= 400. E= -.15997245E+03 F= -.16653160E+03 E0= -.16649509E+03 EK= 0.65591E+01 S
P= 0.00E+00 SK= 0.00E+00
4 T= 399. E= -.15997241E+03 F= -.16652291E+03 E0= -.16648642E+03 EK= 0.65505E+01 S
P= 0.00E+00 SK= 0.00E+00
5 T= 398. E= -.15997236E+03 F= -.16651093E+03 E0= -.16647448E+03 EK= 0.65386E+01 S
P= 0.00E+00 SK= 0.00E+00
6 T= 397. E= -.15997236E+03 F= -.16649575E+03 E0= -.16645934E+03 EK= 0.65234E+01 S
P= 0.00E+00 SK= 0.00E+00
7 T= 396. E= -.15997233E+03 F= -.16647734E+03 E0= -.16644098E+03 EK= 0.65050E+01 S
P= 0.00E+00 SK= 0.00E+00
.
.
.
300 T= 189. E= -.15995987E+03 F= -.16306511E+03 E0= -.16302970E+03 EK= 0.31052E+01 S
P= 0.00E+00 SK= 0.00E+00
301 T= 189. E= -.15995987E+03 F= -.16306314E+03 E0= -.16302774E+03 EK= 0.31033E+01 S
P= 0.00E+00 SK= 0.00E+00
302 T= 189. E= -.15995988E+03 F= -.16306109E+03 E0= -.16302571E+03 EK= 0.31012E+01 S
P= 0.00E+00 SK= 0.00E+00
303 T= 189. E= -.15995987E+03 F= -.16305895E+03 E0= -.16302360E+03 EK= 0.30991E+01 S
P= 0.00E+00 SK= 0.00E+00
304 T= 189. E= -.15995987E+03 F= -.16305673E+03 E0= -.16302140E+03 EK= 0.30969E+01 S
P= 0.00E+00 SK= 0.00E+00
305 T= 189. E= -.15995984E+03 F= -.16305444E+03 E0= -.16301914E+03 EK= 0.30946E+01 S
P= 0.00E+00 SK= 0.00E+00
306 T= 188. E= -.15995982E+03 F= -.16305215E+03 E0= -.16301688E+03 EK= 0.30923E+01 S
P= 0.00E+00 SK= 0.00E+00
307 T= 188. E= -.15995983E+03 F= -.16304987E+03 E0= -.16301464E+03 EK= 0.30900E+01 S
P= 0.00E+00 SK= 0.00E+00
.
.
.
2890 T= 196. E= -.15995242E+03 F= -.16317227E+03 E0= -.16314015E+03 EK= 0.32198E+01 S
P= 0.00E+00 SK= 0.00E+00
2891 T= 196. E= -.15995240E+03 F= -.16317101E+03 E0= -.16313889E+03 EK= 0.32186E+01 S
P= 0.00E+00 SK= 0.00E+00
2892 T= 196. E= -.15995239E+03 F= -.16316972E+03 E0= -.16313761E+03 EK= 0.32173E+01 S
P= 0.00E+00 SK= 0.00E+00
2893 T= 196. E= -.15995237E+03 F= -.16316842E+03 E0= -.16313631E+03 EK= 0.32161E+01 S
P= 0.00E+00 SK= 0.00E+00
2894 T= 196. E= -.15995236E+03 F= -.16316710E+03 E0= -.16313499E+03 EK= 0.32147E+01 S
P= 0.00E+00 SK= 0.00E+00
2895 T= 196. E= -.15995236E+03 F= -.16316576E+03 E0= -.16313365E+03 EK= 0.32134E+01 S
P= 0.00E+00 SK= 0.00E+00
2896 T= 196. E= -.15995233E+03 F= -.16316437E+03 E0= -.16313226E+03 EK= 0.32120E+01 S
P= 0.00E+00 SK= 0.00E+00
2897 T= 196. E= -.15995232E+03 F= -.16316302E+03 E0= -.16313091E+03 EK= 0.32107E+01 S
P= 0.00E+00 SK= 0.00E+00

Thanks for your advice.

Best regards,

Yu

[support_vasp]

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