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Calculation of the bandstructure of Si by means of DFT with different settings
ssh -X EMPA-USER@jump1.empa.ch ssh -X hypatia
module load python/2.7.12
go in the directory where you want to put the exercise and do:
cp /home/cpi/exercise_11.tar ./ tar -xvf exercise_11.tar cd exercise_11
You will find a different directory for each TASK
Please have a look at this web page
http://materialscloud.org/sssp/
where pseudopotentials for different elements of the periodic table can be found. For each pseudopotential several convergence test have been made, the use of the data contained in this webpage can be in general trusted, but additional tests are always a good praxis
Please also have a look at the webpage of quantum-espresso to find a detailed description of input parameters
TASK_0
The batch script run contain the instruction to run a quantum-espresso DFT calculaiton for a conventional cell of Si (ibrav=1 for simple cubic cell). As you can see in the file, 8 atoms are included in the cell of parameter a=5.43A. The primitive cell (ibrav=2 for fcc) would contain only 2 atoms and would not be cubic. The scirpt is ment to run a calculation to optimize the wavefuntion of the system and to compute the total energy. A sinlge k point, Gamma, is used for the summation over the Brillouin Zone.
- Unordered List Itemthe lattice parameter is specified
- Unordered List Itemthe type of lattice (ibrav) is specified
- the coordinates of the atoms are provided in crystal coordinates
- the Monkhorst-Pack grid (in this case only Gamma point) is specifyed for the BZ sums