[CPMD-list] Temperature simulations

[Veronique Van Speybroeck]

Dear ,

my inputfile is given below :
&CPMD
 RESTART LATEST WAVEFUNCTION GEOFILE
 OPTIMIZE GEOMETRY
 TIMESTEP
  5
 MAXSTEP
  3000
 PRINT
  10
 STRUCTURE BONDS ANGLES
 MOVIE SAMPLE
  1
&END

&SYSTEM
 ANGSTROM
 SYMMETRY
 1
 CELL
 6.3 1.0 1.0 0.0 0.0 0.0
 CUTOFF
 25.
&END

&ATOMS
*Cl_VDB_U BINARY NEWF
 LMAX=P
 4
 0.000000    0.000000    0.000000
 3.150000    0.000000    3.150000
 0.000000    3.150000    3.150000
 3.150000    3.150000    0.000000
*019-K-ca-sp-vgrp.uspp BINARY NEWF
 LMAX=P
 4
 3.150000    3.150000    3.150000
 0.000000    0.000000    3.150000
 0.000000    3.150000    0.000000
 3.150000    0.000000    0.000000
&END

&DFT
 LDA CORRELATION PZ
 FUNCTIONAL BP
 GC-CUTOFF
 5.D-5
&END

It is important to set the GC-cutoff to a larger value than for hard 
pseudopotentials.  I used to have problems when I used values of 1D-7 
but with the larger value I never get problems anymore.  Neither for 
lattices as for simple organic systems

Hope this helps.

veronique

Von Braun Nascimento wrote:

>Dear Veronique,
>
>I'm having some problems with geometry optimizations when I use Vanserbilt
>USPP pseudo-potentials. My total static energy versus lattice parameter
>doesn't even presents a minimum. With utilization of  NCPP no problems
>occurr.
>You are successfully using  VDB USPP, at least in the geometry optimization
>step. Have you had any trouble with VDB USSPP ? Is it possible for you to
>send me the input files you have used in the geometry optimization ?
>Thanks in advance.
>Best regards,
>V.B. Nascimento
>
>----- Original Message -----
>From: "Veronique Van Speybroeck" <veronique.vanspeybroeck at rug.ac.be>
>To: <cpmd-list at cpmd.org>
>Sent: Friday, May 09, 2003 5:25 AM
>Subject: [CPMD-list] Temperature simulations
>
>
>  
>
>>Dear All,
>>
>>I have some problems simulating the KCL lattice at elevated temperature.
>> First I did an optimizations on the lattice.  Next I tried to heat up
>>the crystal with the inputfile as given below.  Normally I would expect
>>only small oscillations of the atoms around their equilibrium positions,
>>due to the low temperature.  Strangely the atoms undergo very large
>>variations and I get a totally distorted system.  The temperature in the
>>ENERGIES file raises also drastically.  Can somebody tell me what I do
>>wrong?  The energies file is given in attachment.
>>When I do a MD simulations microcanonically, everything goes fine and
>>the system stays in the minimuum.
>>
>>Thanks in advance
>>
>>veronique
>>
>>
>>&CPMD
>> RESTART LATEST WAVEFUNCTIONS
>> MOLECULAR DYNAMICS CP
>> TIMESTEP
>>  5
>> MAXSTEP
>>  2000
>> PRINT
>>  10
>> TEMPERATURE
>>  5
>> QUENCH BO
>> STRUCTURE BONDS ANGLES
>> MOVIE SAMPLE
>>  1
>>&END
>>
>>&SYSTEM
>> ANGSTROM
>> SYMMETRY
>> 1
>> CELL
>> 6.3 1.0 1.0 0.0 0.0 0.0
>> CUTOFF
>> 25.
>>&END
>>
>>&ATOMS
>>*Cl_VDB_U BINARY NEWF
>> LMAX=P
>> 4
>> 0.000000    0.000000    0.000000
>> 3.150000    0.000000    3.150000
>> 0.000000    3.150000    3.150000
>> 3.150000    3.150000    0.000000
>>*019-K-ca-sp-vgrp.uspp BINARY NEWF
>> LMAX=P
>> 4
>> 3.150000    3.150000    3.150000
>> 0.000000    0.000000    3.150000
>> 0.000000    3.150000    0.000000
>> 3.150000    0.000000    0.000000
>>&END
>>
>>&DFT
>> LDA CORRELATION PZ
>> FUNCTIONAL BP
>> GC-CUTOFF
>> 5.D-5
>>&END
>>
>>--
>>-----------------------------------------------------------------------
>>Dr. ir. Van Speybroeck Veronique
>>Laboratorium voor Theoretische Fysica
>>Universiteit Gent
>>Proeftuinstraat 86
>>9000 Gent
>>Tel +32-9-264.65.58  GSM : +32/474/259767
>>Fax +32-9-264.65.60
>>email : veronique.vanspeybroeck at rug.ac.be
>>http://inwfaxp2.rug.ac.be/~web/onderzoek/proj_3.html
>>-----------------------------------------------------------------------
>>
>>
>>    
>>
>
>
>  
>

-- 
-----------------------------------------------------------------------
Dr. ir. Van Speybroeck Veronique
Laboratorium voor Theoretische Fysica
Universiteit Gent
Proeftuinstraat 86
9000 Gent
Tel +32-9-264.65.58  GSM : +32/474/259767
Fax +32-9-264.65.60
email : veronique.vanspeybroeck at rug.ac.be
http://inwfaxp2.rug.ac.be/~web/onderzoek/proj_3.html
-----------------------------------------------------------------------


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