[CP2K-user] The target temperature cannot be maintained during AIMD simulation process
Tingting Zhu
fengf... at qq.com
Fri Jul 23 11:01:40 UTC 2021
Dear Marcella Iannuzzi
Ok, thank you! I will learn CP2K as your suggestion.
However, for the problem you pointed "the integral error of the equation of
motion is large", I still don't know how to solve it? According to my
current understanding, may I increase the value of EPS_SCF, CUTOFF,
REL_CUTOFF, and decrease the value of TIMESTEP. Do you think it is
appropriate?
For example, ( EPS_DEFAULT 1E-12, EPS_SCF=1.0E*10^6, CUTOFF=350,
REL_CUTOFF=60, TIMESTEP=0.5)
Sincerely
Tingting Zhu
在2021年7月23日星期五 UTC+8 下午4:18:42<Marcella Iannuzzi> 写道：
> Dear Tingting Zhu
>
> I quickly checked your energy file and indeed you have a serious drift in
> the total energy,
> which indicates that the integration of the equations of motion has a
> large error.
> If you do not have experience with ab initio MD, I suggest that you learn
> that first from reference literature.
> The parameters are adjusted until converged results are obtained and known
> properties are reproduced.
>
> Regards
> Marcella
>
>
> On Friday, July 23, 2021 at 9:30:06 AM UTC+2 fe... at qq.com wrote:
>
>> Dear Marcella Iannuzzi
>> Since I am a beginner, although I have read a lot of documents about
>> CP2K, I still lack experience in setting some parameters. In the input
>> file, could you give me some suggestions about the settings of CUTOFF, SCF,
>> EPS_SCF? There are 366 atoms in my system, containing Mg, Al, O, and H.
>> In addition, the input file, out file and corresponding trajectory file
>> that I calculated before are put in the compressed package below.
>>
>> The CP2K version I use is 7.1
>>
>> Thank you very much!
>>
>>
>>
>>
>> 在2021年7月23日星期五 UTC+8 下午2:49:54<Marcella Iannuzzi> 写道：
>>
>>> Dear Tingting Zhu
>>>
>>> One possible explanation is that the error in the forces and in the
>>> integration of the equations of motion is too big.
>>> Some parameters in the input would indicate that, as too large TIMESTEP
>>> and EPS_SCF and too low CUTOFF.
>>> This could be verified from the conservation of the total energy.
>>> Without more information it is difficult to guess.
>>>
>>> Regards
>>> Marcella
>>>
>>> On Friday, July 23, 2021 at 8:34:17 AM UTC+2 fe... at qq.com wrote:
>>>
>>>> Dear all,
>>>>
>>>> I am new to cp2k, I want to use CP2K's kinetics module to simulate the
>>>> adsorption of water on the surface of MgAl2O4 (111) at 973K. However, with
>>>> the increase of simulation time, the temperature keeps increasing, and
>>>> there is no trend to stablize at the target temperature. My input file is
>>>> as follows:
>>>>
>>>> I also tried to modify the TIMECON parameter to 200fs or 400fs, but
>>>> this problem always exists. Any idea whats going wrong here?
>>>>
>>>> I need your help, Please do correct me if any information provided
>>>> seems wrong
>>>>
>>>>
>>>> [image: 200-400 fs.png]
>>>> [image: 200 fs.png]
>>>>
>>>>
>>>> &GLOBAL
>>>> PROJECT MgAl2O4-14W-MD
>>>> PRINT_LEVEL LOW
>>>> RUN_TYPE MD
>>>> &END GLOBAL
>>>>
>>>> &FORCE_EVAL
>>>> METHOD Quickstep
>>>> &SUBSYS
>>>> &CELL
>>>> A 17.33280000 0.00000000 0.00000000
>>>> B 0.00000000 20.01420000 0.00000000
>>>> C 0.00000000 0.00000000 28.56250000
>>>> PERIODIC XYZ #Direction of applied PBC (geometry aspect)
>>>> &END CELL
>>>> &COORD
>>>> Al 0.0000000000 3.3357667100 1.6309187500
>>>> <(630)%20918-7500>
>>>> Al 2.8888577800 <(888)%20857-7800> 8.3393167100
>>>> <(339)%20316-7100> 1.6309187500 <(630)%20918-7500>
>>>> Al 5.7775422200 3.3357667100 1.6309187500
>>>> <(630)%20918-7500>
>>>> Al 8.6664000000 8.3393167100 <(339)%20316-7100>
>>>> 1.6309187500 <(630)%20918-7500>
>>>> Al 11.5552577800 3.3357667100 1.6309187500
>>>> <(630)%20918-7500>
>>>> ............
>>>> &END COORD
>>>> # &VELOCITY #You can set initial atomic velocities in this section
>>>> # &END VELOCITY
>>>> &KIND Al
>>>> ELEMENT Al
>>>> BASIS_SET DZVP-MOLOPT-SR-GTH
>>>> POTENTIAL GTH-PBE
>>>> &END KIND
>>>> &KIND Mg
>>>> ELEMENT Mg
>>>> BASIS_SET DZVP-MOLOPT-SR-GTH
>>>> POTENTIAL GTH-PBE
>>>> &END KIND
>>>> &KIND O
>>>> ELEMENT O
>>>> BASIS_SET DZVP-MOLOPT-SR-GTH
>>>> POTENTIAL GTH-PBE
>>>> &END KIND
>>>> &KIND H
>>>> ELEMENT H
>>>> BASIS_SET DZVP-MOLOPT-SR-GTH
>>>> POTENTIAL GTH-PBE
>>>> &END KIND
>>>> &END SUBSYS
>>>>
>>>> &DFT
>>>> BASIS_SET_FILE_NAME /home/room/data/cp2k-7.1.0/data/BASIS_MOLOPT
>>>> POTENTIAL_FILE_NAME /home/room/data/cp2k-7.1.0/data/POTENTIAL
>>>> # WFN_RESTART_FILE_NAME MgAl2O4-14W-MD-RESTART.wfn
>>>> CHARGE 0 #Net charge
>>>> MULTIPLICITY 1 #Spin multiplicity
>>>> &QS
>>>> EPS_DEFAULT 1E-10 #This is default. Set all EPS_xxx to values
>>>> such that the energy will be correct up to this value
>>>> EXTRAPOLATION ASPC #Extrapolation for wavefunction during e.g.
>>>> MD. ASPC is default, PS also be used
>>>> EXTRAPOLATION_ORDER 3 #Order for PS or ASPC extrapolation. 3 is
>>>> default
>>>> &END QS
>>>> &POISSON
>>>> PERIODIC XYZ #Direction(s) of PBC for calculating electrostatics
>>>> PSOLVER PERIODIC #The way to solve Poisson equation
>>>> &END POISSON
>>>> &XC
>>>> &XC_FUNCTIONAL PBE
>>>> &END XC_FUNCTIONAL
>>>> &VDW_POTENTIAL
>>>> POTENTIAL_TYPE PAIR_POTENTIAL
>>>> &PAIR_POTENTIAL
>>>> PARAMETER_FILE_NAME dftd3.dat
>>>> TYPE DFTD3
>>>> REFERENCE_FUNCTIONAL PBE
>>>> &END PAIR_POTENTIAL
>>>> &END VDW_POTENTIAL
>>>> &END XC
>>>> &MGRID
>>>> CUTOFF 300
>>>> REL_CUTOFF 40
>>>> &END MGRID
>>>> &SCF
>>>> MAX_SCF 500 #Maximum number of steps of inner SCF
>>>> EPS_SCF 1.0E-05 #Convergence threshold of density matrix of inner
>>>> SCF
>>>> # SCF_GUESS RESTART #Use wavefunction from WFN_RESTART_FILE_NAME
>>>> file as initial guess
>>>> &OT
>>>> PRECONDITIONER FULL_KINETIC #FULL_SINGLE_INVERSE is also worth
>>>> to try. FULL_ALL is better but quite expensive for large system
>>>> MINIMIZER DIIS #CG is worth to consider in difficult cases
>>>> LINESEARCH 2PNT #1D line search algorithm for CG. 2PNT is
>>>> default, 3PNT is better but more costly. GOLD is best but very expensive
>>>> &END OT
>>>> &OUTER_SCF
>>>> MAX_SCF 500 #Maximum number of steps of outer SCF
>>>> EPS_SCF 1.0E-05 #Convergence threshold of outer SCF
>>>> &END OUTER_SCF
>>>> &PRINT
>>>> &RESTART #Use "&RESTART OFF" can prevent generating wfn file
>>>> BACKUP_COPIES 0 #Maximum number of backup copies of wfn file
>>>> &END RESTART
>>>> &END PRINT
>>>> &END SCF
>>>> &END DFT
>>>> &END FORCE_EVAL
>>>>
>>>> &MOTION
>>>> &MD
>>>> ENSEMBLE NVT
>>>> STEPS 5000
>>>> TIMESTEP 1.0 #fs. Decrease it properly for high temperature
>>>> simulation
>>>> TEMPERATURE 973 #Initial and maintained temperature (K)
>>>> &THERMOSTAT
>>>> TYPE CSVR
>>>> &CSVR
>>>> TIMECON 200 #Time constant in fs. Smaller/larger results in
>>>> stronger/weaker temperature coupling
>>>> &END CSVR
>>>> &DEFINE_REGION
>>>> LIST 193..366
>>>> &END DEFINE_REGION
>>>> &END THERMOSTAT
>>>> &END MD
>>>> &CONSTRAINT
>>>> &FIXED_ATOMS #Set atoms to be fixed
>>>> COMPONENTS_TO_FIX XYZ #May also be e.g. Z, XY ...
>>>> LIST 1..192
>>>>
>>>> &END FIXED_ATOMS
>>>> &END CONSTRAINT
>>>> &PRINT
>>>> &TRAJECTORY
>>>> &EACH
>>>> MD 1 #Output frequency of geometry
>>>> &END EACH
>>>> FORMAT xyz
>>>> &END TRAJECTORY
>>>> &VELOCITIES
>>>> &EACH
>>>> MD 1 #Output frequency of velocity
>>>> &END EACH
>>>> &END VELOCITIES
>>>> &RESTART
>>>> BACKUP_COPIES 0 #Maximum number of backing up restart file
>>>> &EACH
>>>> MD 10 #Frequency of updating last restart file
>>>> &END EACH
>>>> &END RESTART
>>>> &END PRINT
>>>> &END MOTION
>>>>
>>>> Thanks in advance!
>>>>
>>>> Sincerely
>>>> Tingting Zhu
>>>>
>>>>
>>>>
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