The ABINIT Users Mailing List ( CLOSED )

[Xavier Gonze <gonze@pcpm.ucl.ac.be>]

Dear Stephane,

Please read http://www.abinit.org/Infos_v5.2/users/abinis_help.html#loop
In your case,

ndtset 6    udtset 2 3
ecut1?    3.0     ecut2?   6.0 (or another value)

kptopt?1
tolvrs?1     etc ...


Xavier

On 11 Aug 2006, at 10:32, Stephane BECU wrote:

> Dear all,
>
> I would like to make convergence study on Ecut for a calculation  
> that needs 3 datasets. For example with two Ecut values I would  
> have to define 2x3 = 6 datasets, but I don't know how to declare  
> them. What is the best way to make such double loops? Here is  
> my .in file for only one Ecut... What would be the numerotation for  
> two Ecut for example?
>
> Thanks for your help,
> Stéphane
>
>
> FILE.IN
> ndtset  3
>
> ecut    3.0
>
> #Ground state calculation
>   kptopt1   1             # Automatic generation of k points, taking
>                           # into account the symmetry
>   tolvrs1   1.0d-18       # SCF stopping criterion
>     iscf1   5             # Self-consistent calculation, using  
> algorithm 5
>
> #Response Function calculation : d/dk
>   rfelfd2   2             # Activate the calculation of the d/dk  
> perturbation
>    rfdir2   1 0 0         # Need to consider the perturbation in  
> the x-direction only due to the high symmetry of the Si crystal. In  
> general, just use rfdir 1 1 1.In the present version of ABINIT  
> (v4.6), symmetry cannot be used to reduce the number of ddk  
> perturbations.
>
>     nqpt2   1
>      qpt2   0.0 0.0 0.0   # This is a calculation at the Gamma point
>
>   getwfk2   -1            # Uses as input the output wf of the  
> previous dataset
>
>   kptopt2   2             # Automatic generation of k points,
>                           # using only the time-reversal symmetry  
> to decrease
>                           # the size of the k point set.
>
>     iscf2  -3             # The d/dk perturbation must be treated
>                           # in a non-self-consistent way
>   tolwfr2   1.0d-22       # Must use tolwfr for non-self-consistent  
> calculations
>                           # Here, the value of tolwfr is very low.
>
> #Response Function calculation : electric field perturbation and  
> phonons
>   rfphon3   1             # Activate the calculation of the atomic  
> dispacement perturbations
>  rfatpol3   1 1           # All the atoms will be displaced
>   rfelfd3   3             # Activate the calculation of the  
> electric field perturbation
>    rfdir3   1 1 1         # All directions are selected. However,  
> symmetries will be used to decrease
>                           # the number of perturbations, so only  
> the x electric field is needed
>                           # (and this explains why in the second  
> dataset, rfdir was set to 1 0 0).
>
>     nqpt3   1
>      qpt3   0.0 0.0 0.0   # This is a calculation at the Gamma point
>
>   getwfk3   -2            # Uses as input wfs the output wfs of the  
> dataset 1
>   getddk3   -1            # Uses as input ddk wfs the output of the  
> dataset 2
>
>   kptopt3   2             # Automatic generation of k points,
>                           # using only the time-reversal symmetry  
> to decrease
>                           # the size of the k point set.
>   tolvrs3   1.0d-8
>     iscf3   5             # Self-consistent calculation, using  
> algorithm 5
>
>
> ###################################################################### 
> #
> #Common input variables
>
> #Definition of the unit cell
> acell 3*10.217
> rprim  0.0  0.5  0.5   # FCC primitive vectors (to be scaled by acell)
>        0.5  0.0  0.5
>        0.5  0.5  0.0
>
> #Definition of the atom types
> ntypat 1
> znucl 14
>
> #Definition of the atoms
> natom 2                # There are two atoms
> typat 1 1         # They both are of type 1, that is, Silicon.
> xred              # This keyword indicate that the location of the  
> atoms
>                   # will follow, one triplet of number for each atom
>    0.0  0.0  0.0  # Triplet giving the REDUCED coordinate of atom 1.
>    1/4  1/4  1/4  # Triplet giving the REDUCED coordinate of atom 2.
>
> #Gives the number of band, explicitely (do not take the default)
> nband  4
>
> #Exchange-correlation functional
> ixc 1             # LDA Teter Pade parametrization
>
>
> #Definition of the k-point grid
> nshiftk  4
> shiftk   0.5 0.5 0.5  # These shifts will be the same for all grids
>          0.5 0.0 0.0
>          0.0 0.5 0.0
>          0.0 0.0 0.5
> ngkpt   8 8 8
>
>
> #Definition of the SCF procedure
> nstep 20               # Maximal number of SCF cycles
> diemac 12.0