[Pw_forum] question about the stress in relax process
Wang Di
didi5158 at gmail.com
Mon Sep 20 12:14:07 CEST 2010
I am very sorry that the input file was wrong, the relax input file is the
similar to the file.
&CONTROL
calculation = 'relax' ,
restart_mode = 'from_scratch' ,
wf_collect = .true. ,
outdir = '/lustre/AIOFM/gxgu/workLCAF/6/temp/' ,
wfcdir = '/lustre/AIOFM/gxgu/workLCAF/6/wftemp/' ,
pseudo_dir = '/home/AIOFM/gxgu/work/NCPP/' ,
prefix = 'LCAF' ,
etot_conv_thr = 1.0D-6 ,
forc_conv_thr = 1.0D-4 ,
nstep = 100 ,
tstress = .true. ,
tprnfor = .true. ,
dipfield = .true. ,
/
&SYSTEM
ibrav = 4,
celldm(1) = 9.4264,
celldm(3) = 1.9287,
nat = 18,
ntyp = 4,
ecutwfc = 30 ,
ecutrho = 120 ,
nosym = .false. ,
/
&ELECTRONS
electron_maxstep = 100,
conv_thr = 1.0D-8 ,
/
&IONs
ion_dynamics = 'bfgs' ,
/
ATOMIC_SPECIES
Li 6.94100 03-Li.LDA.fhi.UPF
Al 26.98154 13-Al.LDA.fhi.UPF
Ca 40.07800 20-Ca.LDA.fhi.UPF
F 18.99840 09-F.LDA.fhi.UPF
ATOMIC_POSITIONS crystal
Li 0.333333333 0.666666667 0.250000000
Li -0.333333333 -0.666666667 -0.250000000
F 0.375499994 0.031899999 0.143800005
F -0.031899999 0.343599993 0.143800005
F -0.343599993 -0.375499993 0.143800005
F -0.031899999 -0.375499993 0.356199994
F -0.343599993 0.031899999 0.356199994
F 0.375499993 0.343599993 0.356199994
F -0.375499993 -0.031899998 -0.143800005
F 0.031899999 -0.343599993 -0.143800005
F 0.343599993 0.375499993 -0.143800005
F 0.031899999 0.375499993 0.643800005
F 0.343599993 -0.031899999 0.643800005
F -0.375499993 -0.343599993 0.643800005
Al 0.666666667 0.333333333 0.250000000
Al -0.666666667 -0.333333333 -0.250000000
Ca 0.000000000 0.000000000 0.000000000
Ca 0.000000000 0.000000000 0.500000000
K_POINTS automatic
16 16 16 0 0 0
2010/9/20 mohnish pandey <mohnish.iitk at gmail.com>
> Dear Wang,
> Are you sure that this is your input file? Because the
> calculation flag says it is "scf" ..Which will not definitely do the relax
> calculation....
>
>
> On Mon, Sep 20, 2010 at 3:32 PM, Wang Di <didi5158 at gmail.com> wrote:
>
>> Dear Mohnish:
>> I have used the 'vc-relax' process optimized the cell parameter, however,
>> the result were seem to deviate from the initial value (experimental value)
>> too much.The aim of the structure optimizes is for calculating the Raman
>> spectra of the structure, I think the bad structure ( not coincide to the
>> experiment) is hard to got the true spectra. So I don't how to deal with the
>> case. According to your experience, what should I do for the next step?
>>
>> Thank you, dear Mohnish, for your kind help.
>>
>>
>>
>> 2010/9/20 mohnish pandey <mohnish.iitk at gmail.com>
>>
>> Dear Wang,
>>> The 'relax' process optimizes the structure within
>>> given geometric constraint. It does'nt care for stress. It minimizes force
>>> only in the given constraint. If you want to minimize the stress also you
>>> have to do 'vc-relax' calculation, It will give you what you want.
>>>
>>> On Mon, Sep 20, 2010 at 11:37 AM, Wang Di <didi5158 at gmail.com> wrote:
>>>
>>>> Dear all
>>>>
>>>> I perform the relax calculate to the crystal structure. After 11 step
>>>> bfgs, the total force and total scf correction had reach to the criterion,
>>>> however, the total stress was so big P=-3443.87. I have no idea about deal
>>>> with the case, could anyone give some advices? Thanks in advance.
>>>>
>>>> the input file
>>>> : &CONTROL
>>>> calculation = 'scf' ,
>>>> restart_mode = 'from_scratch' ,
>>>> wf_collect = .true. ,
>>>> outdir = '/lustre/AIOFM/gxgu/workLCAF/5/temp/' ,
>>>> wfcdir = '/lustre/AIOFM/gxgu/workLCAF/5/wftemp/' ,
>>>> pseudo_dir = '/home/AIOFM/gxgu/work/NCPP/' ,
>>>> prefix = 'LCAF' ,
>>>> etot_conv_thr = 1.0D-7 ,
>>>> forc_conv_thr = 1.0D-6 ,
>>>> nstep = 100 ,
>>>> tstress = .true. ,
>>>> tprnfor = .true. ,
>>>> dipfield = .true. ,
>>>> /
>>>> &SYSTEM
>>>> ibrav = 4,
>>>> celldm(1) = 9.42432151,
>>>> celldm(3) = 1.94804220,
>>>> nat = 18,
>>>> ntyp = 4,
>>>> ecutwfc = 30 ,
>>>> ecutrho = 120 ,
>>>> nosym = .false. ,
>>>> /
>>>> &ELECTRONS
>>>> electron_maxstep = 100,
>>>> conv_thr = 1.0D-10 ,
>>>> /
>>>> ATOMIC_SPECIES
>>>> Li 6.94100 03-Li.LDA.fhi.UPF
>>>> Al 26.98154 13-Al.LDA.fhi.UPF
>>>> Ca 40.07800 20-Ca.LDA.fhi.UPF
>>>> F 18.99840 09-F.LDA.fhi.UPF
>>>> ATOMIC_POSITIONS crystal
>>>> Li 0.333333333 0.666666667 0.250000000
>>>> Li -0.333333333 -0.666666667 -0.250000000
>>>> F 0.389997 0.045970 0.148326
>>>> F -0.045970 0.344027 0.148326
>>>> F -0.344027 -0.389997 0.148326
>>>> F -0.045970 -0.389997 0.351674
>>>> F -0.344027 0.045970 0.351674
>>>> F 0.389997 0.344027 0.351674
>>>> F -0.389997 -0.045970 -0.148326
>>>> F 0.045970 -0.344027 -0.148326
>>>> F 0.344027 0.389997 -0.148326
>>>> F 0.045970 0.389997 0.648326
>>>> F 0.344027 -0.045970 0.648326
>>>> F -0.389997 -0.344027 0.648326
>>>> Al 0.666666667 0.333333333 0.250000000
>>>> Al -0.666666667 -0.333333333 -0.250000000
>>>> Ca 0.000000000 0.000000000 0.000000000
>>>> Ca 0.000000000 0.000000000 0.500000000
>>>> K_POINTS automatic
>>>> 16 16 16 0 0 0
>>>>
>>>> best regart
>>>>
>>>> Wang Di
>>>>
>>>> --
>>>> -----------------------------------------------------------------
>>>> *Wang Di**
>>>> The Crystal Lab,*
>>>> *AnHui Institute of Optics and Fine Mechanics, ***
>>>> *Chinese Academy of Sciences,**
>>>> No350. , Shushanhu Road, Hefei, 230031, China**,
>>>> E-mail: didi5158 @gmail.ocm** ,*
>>>> -----------------------------------------------------------------
>>>>
>>>> _______________________________________________
>>>> Pw_forum mailing list
>>>> Pw_forum at pwscf.org
>>>> http://www.democritos.it/mailman/listinfo/pw_forum
>>>>
>>>>
>>>
>>>
>>> --
>>> Regards,
>>> MOHNISH,
>>> -----------------------------------------------------------------
>>> Mohnish Pandey
>>> Y6927262,5th Year dual degree student,
>>> Department of Chemical Engineering,
>>> IIT KANPUR, UP, INDIA
>>> +919235721300
>>> -----------------------------------------------------------------
>>>
>>> _______________________________________________
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://www.democritos.it/mailman/listinfo/pw_forum
>>>
>>>
>>
>>
>> --
>> -----------------------------------------------------------------
>> *Wang Di**
>> The Crystal Lab,*
>> *AnHui Institute of Optics and Fine Mechanics, ***
>> *Chinese Academy of Sciences,**
>> No350. , Shushanhu Road, Hefei, 230031, China**,
>> E-mail: didi5158 @gmail.ocm** ,*
>> -----------------------------------------------------------------
>>
>> _______________________________________________
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://www.democritos.it/mailman/listinfo/pw_forum
>>
>>
>
>
> --
> Regards,
> MOHNISH,
> -----------------------------------------------------------------
> Mohnish Pandey
> Y6927262,5th Year dual degree student,
> Department of Chemical Engineering,
> IIT KANPUR, UP, INDIA
> +919235721300
> -----------------------------------------------------------------
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>
>
--
-----------------------------------------------------------------
*Wang Di**
The Crystal Lab,*
*AnHui Institute of Optics and Fine Mechanics, ***
*Chinese Academy of Sciences,**
No350. , Shushanhu Road, Hefei, 230031, China**,
E-mail: didi5158 @gmail.ocm** ,*
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