[Pw_forum] Temperature continuously going down in cp.x run

vega lew quantumdft at gmail.com
Fri Nov 27 14:02:56 CET 2009


Dear Somesh,

do you think this is reasonable when all the atoms in my system is at their
equilibrium position?

vega

On Fri, Nov 27, 2009 at 4:33 AM, Somesh Kumar Bhattacharya <
somesh.kb at gmail.com> wrote:

> Dear Vega,
>
> something is wrong in your simulation. I don't know exactly what. The
> constant of motion is changing by 0.01 hartree  which is quite significant.
>
> Regards,
>
> Somesh
>
>
> On Fri, Nov 27, 2009 at 1:26 PM, vega lew <quantumdft at gmail.com> wrote:
>
>> Dear friend,
>>
>> thank you for you information.
>> I attach the file in the list. In the file, I find the 8th column is not
>> remain the same.
>>
>> thank you again.
>>
>> vega
>>
>>
>> On Fri, Nov 27, 2009 at 4:04 AM, Somesh Kumar Bhattacharya <
>> somesh.kb at gmail.com> wrote:
>>
>>> Dear Vega,
>>>
>>> The CP program prints different energy in the output file *.evp. In this
>>> file the eighth column is the constant of motion which should remain a
>>> constant. Plot this eighth column vs the timesteps and see what fluctuations
>>> are you getting in the plot.
>>>
>>> This is I guess what Stefano asked you.
>>>
>>> Regards,
>>>
>>> Somesh
>>>
>>>
>>> On Fri, Nov 27, 2009 at 12:42 PM, vega lew <quantumdft at gmail.com> wrote:
>>>
>>>> Dear sir,
>>>>
>>>> Did you ask whether the (etot+ekinc) conserve during the dynamic
>>>> process?
>>>>
>>>> I sum the corresponding columns. I found it is not changing very much.
>>>>
>>>> For example, the (ekinc+ etot) is -4369.40879 (-4369.44669+0.0379) at
>>>> 2200 step.
>>>> Then it changes to -4369.41514 (-4369.45479+0.03965) at 2300 step.
>>>> And it sometimes goes a little up and sometimes a little down. But the
>>>> value is in range of
>>>> -4369.41 and -4369.45.
>>>>
>>>> thank you for reading.
>>>>
>>>> vega
>>>>
>>>>
>>>>
>>>> On Fri, Nov 27, 2009 at 2:02 AM, Stefano de Gironcoli <
>>>> degironc at sissa.it> wrote:
>>>>
>>>>> is the total  (kinetic + potential)  energy conserved ?
>>>>> stefano
>>>>>
>>>>> vega lew wrote:
>>>>> > dear all,
>>>>> >
>>>>> > I want to calculate certain heterogeneous reaction on a solid
>>>>> surface.
>>>>> > First input the initial structure from previous pw.x relaxations.
>>>>> > Second I fixed ions and let electron damping calculation run;
>>>>> > Then un-fixed the ions and let both electron  and ions damping
>>>>> > calculations run.
>>>>> > Third I gave a random motion to the atoms in the system with
>>>>> > amprp(1)~(3) = 0.01
>>>>> > and then repeated second step to bring the system to the ground
>>>>> state.
>>>>> > Fourth I added temperature (300K) to the system, using verlet
>>>>> schedule.
>>>>> >
>>>>> > But the temperature continuously going down, from 1000K to 150K
>>>>> during
>>>>> > the fisrt 3000 steps.
>>>>> > I think there might be something wrong with my cp.x calcuation.
>>>>> > Do you think the amprp(1)~(3) = 0.01 of random motion is too small?
>>>>> >
>>>>> > Here is the input of my dynamics process,
>>>>> >  &CONTROL
>>>>> >
>>>>> >                        title = 'CP'
>>>>> > ,
>>>>> >                  calculation = 'cp'
>>>>> > ,
>>>>> >                 restart_mode = 'restart'
>>>>> > ,
>>>>> >                       outdir = '/disk5/nanjing/vega/cp/300/' ,
>>>>> >                       wfcdir = '/tmp/'
>>>>> > ,
>>>>> >                   pseudo_dir =
>>>>> > '/home/software/nanjing/vega/espresso-4.0.1/pseudo/' ,
>>>>> >                       prefix = 'cp_molecular' ,
>>>>> >                        nstep = 99999 ,
>>>>> >                           dt = 10,
>>>>> >                       iprint = 5,
>>>>> >                        isave =
>>>>> > 150,
>>>>> >  /
>>>>> >
>>>>> >  &SYSTEM
>>>>> >
>>>>> >                        ibrav =
>>>>> > 8,
>>>>> >                    celldm(1) =24.8624,
>>>>> >                    celldm(2) = 0.8520,
>>>>> >                    celldm(3) = 1.6964,
>>>>> >                          nat =
>>>>> > 147,
>>>>> >                         ntyp = 3,
>>>>> >                         nr1b = 20,
>>>>> >                         nr2b = 20,
>>>>> >                         nr3b = 20,
>>>>> >                         nbnd =
>>>>> > 630,
>>>>> >                    ecutwfc   =   30,
>>>>> >                    ecutrho   =  300,
>>>>> >  /
>>>>> >
>>>>> >
>>>>> >  &ELECTRONS
>>>>> >            electron_dynamics = 'verlet',
>>>>> >  /
>>>>> >
>>>>> >  &IONS
>>>>> >
>>>>> >                 ion_dynamics = 'verlet'
>>>>> >              ion_temperature = 'nose',
>>>>> >                        tempw = 300,
>>>>> >  /
>>>>> > ..................
>>>>> > ..................
>>>>> >
>>>>> > best wishes,
>>>>> >
>>>>> > vega
>>>>> >
>>>>> > --
>>>>> >
>>>>> ==================================================================================
>>>>> > Vega Lew ( weijia liu)
>>>>> > Graduate student
>>>>> > State Key Laboratory of Materials-oriented Chemical Engineering
>>>>> > College of Chemistry and Chemical Engineering
>>>>> > Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
>>>>> >
>>>>> ******************************************************************************************************************
>>>>> > Email: vegalew at gmail.com <mailto:vegalew at gmail.com>
>>>>> > Office: Room A705, Technical Innovation Building, Xinmofan Road 5#,
>>>>> > Nanjing, Jiangsu, China
>>>>> >
>>>>> ******************************************************************************************************************
>>>>> >
>>>>> >
>>>>> ------------------------------------------------------------------------
>>>>> >
>>>>> > _______________________________________________
>>>>> > Pw_forum mailing list
>>>>> > Pw_forum at pwscf.org
>>>>> > http://www.democritos.it/mailman/listinfo/pw_forum
>>>>> >
>>>>>
>>>>> _______________________________________________
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>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>>
>>>> ==================================================================================
>>>> Vega Lew ( weijia liu)
>>>> Graduate student
>>>> State Key Laboratory of Materials-oriented Chemical Engineering
>>>> College of Chemistry and Chemical Engineering
>>>> Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
>>>>
>>>> ******************************************************************************************************************
>>>> Email: vegalew at gmail.com
>>>> Office: Room A705, Technical Innovation Building, Xinmofan Road 5#,
>>>> Nanjing, Jiangsu, China
>>>> ******************************************************************************************************************
>>>>
>>>>
>>>> _______________________________________________
>>>> Pw_forum mailing list
>>>> Pw_forum at pwscf.org
>>>> http://www.democritos.it/mailman/listinfo/pw_forum
>>>>
>>>>
>>>
>>>
>>> --
>>> Somesh Kr. Bhattacharya
>>> Post Doctoral Fellow
>>> Room No. 263,
>>> Leonardo Building,
>>> The Abdus Salam International Centre for Theoretical Physics
>>> Strada Costiera, 11
>>> I-34014 Trieste
>>> Italy
>>> Phone: +39-040-2240399
>>>
>>> http://portal.ictp.it/cmsp/members/postdoctoral-fellows/somesh-kumar-bhattacharya/
>>>
>>> _______________________________________________
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://www.democritos.it/mailman/listinfo/pw_forum
>>>
>>>
>>
>>
>> --
>>
>> ==================================================================================
>> Vega Lew ( weijia liu)
>> Graduate student
>> State Key Laboratory of Materials-oriented Chemical Engineering
>> College of Chemistry and Chemical Engineering
>> Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
>>
>> ******************************************************************************************************************
>> Email: vegalew at gmail.com
>> Office: Room A705, Technical Innovation Building, Xinmofan Road 5#,
>> Nanjing, Jiangsu, China
>> ******************************************************************************************************************
>>
>>
>> _______________________________________________
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://www.democritos.it/mailman/listinfo/pw_forum
>>
>>
>
>
> --
> Somesh Kr. Bhattacharya
> Post Doctoral Fellow
> Room No. 263,
> Leonardo Building,
> The Abdus Salam International Centre for Theoretical Physics
> Strada Costiera, 11
> I-34014 Trieste
> Italy
> Phone: +39-040-2240399
>
> http://portal.ictp.it/cmsp/members/postdoctoral-fellows/somesh-kumar-bhattacharya/
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>
>


-- 
==================================================================================
Vega Lew ( weijia liu)
Graduate student
State Key Laboratory of Materials-oriented Chemical Engineering
College of Chemistry and Chemical Engineering
Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
******************************************************************************************************************
Email: vegalew at gmail.com
Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing,
Jiangsu, China
******************************************************************************************************************
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