question on scaling velocities in MD

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luke419
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Posts: 37
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License Nr.: 141 (vasp.4.6+paw)

question on scaling velocities in MD

#1 Post by luke419 » Wed Aug 22, 2012 2:25 pm

I'd like to scale velocities every one or five times to the desired temperature in MD.
For this, I've compiled VASP using tbdyn option and performed MD simulation using the following commands.

PREC = low
ENCUT = 400
LREAL = A
IBRION = 0
SMASS = -1
NSW = 100
MDALGO = 2
TEBEG = 300 ! temp in beginning
TEEND = 300 ! tem in end
ISYM = 0
POTIM = 0.5
LREAL = A
IALGO = 48
NBLOCK = 1
LWAVE = .FALSE.
LCHARG = .FALSE.
ISMEAR = 0
SIGMA = 0.1

I tested both MDALGO = 2 and 0 for either of NBLOCK = 1 or 5. However, all of themt ddin't show the scaled result of temperature as follows (NBLOCK = 1).

kinetic Energy EKIN = 6.165656 (temperature 300.00 K)
kinetic Energy EKIN = 6.146805 (temperature 299.08 K)
kinetic Energy EKIN = 6.109881 (temperature 297.28 K)
kinetic Energy EKIN = 6.055132 (temperature 294.62 K)
kinetic Energy EKIN = 5.983025 (temperature 291.11 K)
kinetic Energy EKIN = 5.894058 (temperature 286.78 K)
kinetic Energy EKIN = 5.789296 (temperature 281.68 K)
kinetic Energy EKIN = 5.669807 (temperature 275.87 K)
kinetic Energy EKIN = 5.536785 (temperature 269.40 K)
kinetic Energy EKIN = 5.391515 (temperature 262.33 K)
kinetic Energy EKIN = 5.235357 (temperature 254.73 K)
kinetic Energy EKIN = 5.069987 (temperature 246.69 K)
kinetic Energy EKIN = 4.896846 (temperature 238.26 K)
...

What's wrong with it? I think it is complied corrrectly but if there is a special thing to be considered in the complication, please, let me know of it. In addition, can I see whether SMASS=-1 works really (that is, the validation of correct comlication with tbdyn option) in OUTCAR file?

Best regards,

Luke



<span class='smallblacktext'>[ Edited ]</span>
Last edited by luke419 on Wed Aug 22, 2012 2:25 pm, edited 1 time in total.

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Re: question on scaling velocities in MD

#2 Post by support_vasp » Thu Sep 12, 2024 8:21 am

Hi,

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