Hi....

You should do the calculations by defining unit cell instead of permitive
unit cell. Then define supercell.to get 64 atoms.
Thanks
On 6 Jul 2015 18:11, "毛飞" <[email protected]> wrote:

> Dear Siesta Users
>
>
>
> I would like to calculate the band structure of LiF crystal. The
> considered LiF are composed by 64 atoms, and the band structure is
> calculated along the Γ->X->W->Γ lines. I have encountered some problems
> in writing the input file.
>
>
>
> 1.      I want to simulate the LiF as bulk material, when I choose the
> magnitudes of
>
> the simulation cell (defined by block LatticeVectors) as the same as the
> considered LiF system, the output shows some atoms are too close. So I
> defined a bigger simulation cell (the distance between the edges of LiF and
> the boundary of the simulation cell is about 2 Å), as the periodic boundary
> condition is always employed in Siesta code, there is a vacuum area between
> the LiF system and its mirror images, does the empty area affect the bulk
> characters?
>
>
>
> 2. In my calculations, the number of k points sampling in Brillouin zone,
> it seems to me that, is determined by the number of points defined in block
> BandLines. So does the block kgrid_Monkhorst_Pack paly a role in my
> calculation?
>
>
>
> Any comment is appreciated, and thank you in advance.
>
>
>
> Sincerely
>
>
>
> Fei Mao
>
> USC
>
>
>
> The input file is followed.
>
>
>
> SystemName          bulk.LiF
>
> SystemLabel          bulk_LiF
>
>
>
> NumberOfAtoms       64
>
> NumberOfSpecies     2
>
>
>
> %block ChemicalSpeciesLabel
>
>  1    3    Li
>
>  2    9    F
>
> %endblock ChemicalSpeciesLabel
>
>
>
> # basis
>
> PAO.BasisSize       DZP
>
> PAO.EnergyShift     200 meV
>
>
>
> LatticeConstant    4.10 Ang   # Lattice constant alat
>
>
>
> %block LatticeVectors               # Lattice vectors, in units of
> latticeconstant
>
>  4.0      0.0       0.0
>
>  0.0      4.0       0.0
>
>  0.0      0.0       4.0
>
> %endblock LatticeVectors
>
>
>
> %block kgrid_Monkhorst_Pack
>
>  2 0 0   0.0
>
>  0 2 0   0.0
>
>  0 0 2   0.0
>
> %endblock kgrid_Monkhorst_Pack
>
>
>
>
>
> BandLinesScale  ReciprocalLatticeVectors
>
>
>
> %block BandLines
>
> 1     0.0   0.0   0.0     # Gamma-point
>
> 20    0.5   0.0   0.5     # X-point
>
> 30    0.5   0.25  0.75    # W-point
>
> 30    0.0   0.0   0.0     # Gamma-point
>
> %endblock BandLines
>
>
>
>
>
> %block  ProjectedDensityOfStates
>
>  -20 10 0.1  300    eV
>
> %endblock ProjectedDensityOfStates
>
>
>
> MeshCutoff          300.0 Ry
>
>
>
> # SCF options
>
> MaxSCFIterations      100           # Maximum number of SCF iter
>
> DM.NumberPulay         3            # One Pulay every 3 iter
>
> DM.MixingWeight       0.35         # New DM amount for next SCF cycle
>
> DM.Tolerance          5.d-4         # Tolerance in maximum difference
>
>
>
> SolutionMethod        diagon        # OrderN or Diagon
>
> OccupationFunction    FD
>
> ElectronicTemperature  25 meV       # Temp. for Fermi smearing
>
>
>
>
>
> # structural infomation
>
> AtomCoorFormatOut Ang
>
>
>
> # output information
>
> WriteCoorXmol T
>
> WriteMDXmol T
>
> WriteForces T
>
>
>
> WriteKpoints            .true.
>
> WriteEigenvalues        .true.
>
> WriteKbands             .true.
>
> WriteBands              .true.
>
> WriteMullikenPop        1
>
>
>
> # options for MD
>
> MD.MaxForceTol          0.01 eV/Ang
>
> MD.TypeOfRun CG
>
> MD.NumCGSteps 400
>
> MD.Broyden.History.Steps 6
>
> MD.Broyden.Initial.Inverse.Jacobian 1.0
>
>
>
> # options for continue
>
> # MD.UseSaveCG T                        # neccessary!
>
> # MD.UseSaveXV T                        # neccessary!
>
> # DM.UseSaveDM          true            # to use continuae..ion files
>
>
>
>
>
> AtomicCoordinatesFormat Ang
>
> %block AtomicCoordinatesAndAtomicSpecies
>
>    2.137021       6.089057      -5.994028               2
>
>    2.036554       2.027964      -5.945600               1
>
>    2.039835       5.953723      -2.024337               1
>
>    2.147364       2.056847      -2.009531               2
>
>    5.895380       5.857752      -5.881708               1
>
>    6.074761       1.931439      -5.993322               2
>
>    6.051639       5.949852      -2.013944               2
>
>    5.963747       2.022693      -2.026392               1
>
>    2.129653       6.096888       2.008118               2
>
>    2.040599       2.032355       2.028040               1
>
>    2.063950       5.933649       5.923014               1
>
>    2.146574       2.055140       5.999910               2
>
>    5.941415       5.910826       2.052174               1
>
>    6.085698       1.925561       2.008577               2
>
>    6.014877       5.895361       5.967268               2
>
>    5.938924       2.053165       5.922581               1
>
>   -5.895364       6.014879      -5.967268               2
>
>   -5.933649       2.063950      -5.923014               1
>
>   -5.910826       5.941414      -2.052174               1
>
>   -6.096889       2.129653      -2.008118               2
>
>   -2.053165       5.938924      -5.922581               1
>
>   -2.055140       2.146574      -5.999911               2
>
>   -1.925561       6.085697      -2.008577               2
>
>   -2.032355       2.040599      -2.028040               1
>
>    2.055140      -2.146574      -5.999911               2
>
>    2.053164      -5.938925      -5.922581               1
>
>    2.032355      -2.040599      -2.028040               1
>
>    1.925561      -6.085697      -2.008577               2
>
>    5.933649      -2.063950      -5.923014               1
>
>    5.895365      -6.014880      -5.967269               2
>
>    6.096889      -2.129653      -2.008118               2
>
>    5.910826      -5.941414      -2.052174               1
>
>    2.056847      -2.147365       2.009531               2
>
>    2.022692      -5.963746       2.026392               1
>
>    2.027964      -2.036554       5.945600               1
>
>    1.931439      -6.074760       5.993321               2
>
>    5.953723      -2.039835       2.024337               1
>
>    5.949852      -6.051639       2.013944               2
>
>    6.089057      -2.137021       5.994028               2
>
>    5.857752      -5.895380       5.881708               1
>
>   -5.949852       6.051639       2.013944               2
>
>   -5.953723       2.039835       2.024337               1
>
>   -5.857752       5.895380       5.881708               1
>
>   -6.089057       2.137022       5.994028               2
>
>   -2.022692       5.963746       2.026392               1
>
>   -2.056847       2.147365       2.009531               2
>
>   -1.931439       6.074760       5.993321               2
>
>   -2.027964       2.036554       5.945600               1
>
>   -6.074760      -1.931439      -5.993322               2
>
>   -5.895380      -5.857752      -5.881708               1
>
>   -5.963747      -2.022693      -2.026392               1
>
>   -6.051639      -5.949852      -2.013945               2
>
>   -2.036554      -2.027964      -5.945600               1
>
>   -2.137021      -6.089057      -5.994028               2
>
>   -2.147364      -2.056847      -2.009531               2
>
>   -2.039835      -5.953723      -2.024337               1
>
>   -6.085698      -1.925561       2.008577               2
>
>   -5.941415      -5.910826       2.052174               1
>
>   -5.938924      -2.053165       5.922581               1
>
>   -6.014877      -5.895360       5.967268               2
>
>   -2.040599      -2.032355       2.028040               1
>
>   -2.129653      *******           *****                      2
>
>   -2.146574      *****               *****                      2
>
>   -2.063950      *****               5*****                    1
>
> %endblock AtomicCoordinatesAndAtomicSpecies
>
>
>
>
>
>

Responder a