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
