Bandsctructure calculation

Bandstructure calculation for Si

Input files

atom.config

        2
 LATTICE
      0.00000000     2.71535000     2.71535000
      2.71535000     0.00000000     2.71535000
      2.71535000     2.71535000     0.00000000
 POSITION
  14     0.00000000     0.00000000     0.00000000 0 0 0
  14     0.25000000     0.25000000     0.25000000 0 0 0

etot.input

   1 4
   JOB = NONSCF
   IN.PSP1 = Si.SG15.PBE.UPF
   IN.ATOM = atom.config
   ECUT = 50
   IN.VR = T
   IN.KPT = T

Note

1. Read IN.VR from previous SCF calculation. To copy OUT.VR and OUT.FERMI from the SCF calculation of example Si SCF Calculation to your current working drectory and rename IN.VR.
2. IN.KPT is the k-points file which PWmat will use for band structure calculation, one can use "split_kp.x" utility to get it. You should prepare an input file for "split_kp.x", which can be named "gen.kpt":

      BAND                    # COMMENT line
      10                      # number of k-points between X and R
      0.500  0.000  0.000  X  # reciprocal coordinates; label 'X' for X point
      0.500  0.500  0.500  R
      10
      0.500  0.500  0.500  R
      0.500  0.500  0.000  M
      10
      0.500  0.500  0.000  M
      0.000  0.000  0.000  G
      10
      0.000  0.000  0.000  G
      0.500  0.500  0.500  R

      split_kp.x gen.kpt

After running "split_kp.x gen.kpt", it will generate "IN.KPT" and "HIGH_SYMMETRY_POINT" (high-symmetry points information) files.

Si.SG15.PBE.UPF

提示

Si.SG15.PEB.UPF is the pseudopotential file.

Calculations

1. You can submit PWmat tasks in different ways:

   mpirun -np 4 PWmat | tee output

Note

Run the command directly

---

   #!/bin/bash
   #PBS -N SCF
   #PBS -l nodes=1:ppn=4
   #PBS -q batch
   #PBS -l walltime=100:00:00

   ulimit -s unlimited
   cd $PBS_O_WORKDIR

   mpirun -np 4 PWmat | tee output

Note

Submit the task with a pbs script

2. After NONSCF calculation, you can run "plot_band_structure.x" to obtain band structure in your current working directory. Then it will generate the following files: bandstructure.eps, bandstructure.png, bandstructure.pdf and bandstructure_1.txt (the data file of band structure), which can be used to plot band by origin or gnuplot. Note, for "spin=2", another data file bandstructure_2.txt will be generated.

   plot_band_structure.x

Download

Si_Band_Cal