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Simulation of STM and AFM images for a graphene nanoribbons adsorbed on a metallic substrate

connect to hypatia:
ssh -X
ssh -X hypatia
module load python/2.7.12 

go to your scratch directory:

cd /mnt/scratch/your_username

and copy there the tar file of the exercise:

cp /home/cpi/exercise_12.tar ./
tar -xvf exercise_12.tar
cd exercise_12

We consider two possible chemical terminations for a finite size 7-AGNR. In TASK_1 the ribbon is terminated with a C-H2 bonding while in TASK_2 the termination is C-H The additional H atom present at the termini of the ribbon of TASK_1 will suppress the spin polarized edge states that are evident in the ribbon of TASK_2


Have a look to the cp2k input file cp2k.inp used to obtain quickly the optimized geometry of a ribbon adsorbed on a Au substrate. The ribbon is modelled within DFTB (similar to tight binding) while the substrate is modelled via Embedded Atom Model. An empirical potential in teh form of C6/R^6 plus a pauli repulsion is added to couple the adsorbate/substrate systems.

Two geometry fiels are present: and The input needs both of them.

Have a look at the geometry of the system using ASE:

In [1]: from import read

In [2]: from ase.visualize import view

In [3]: s=read("")

In [4]: view(s)

In [5]: exit()
submit the geometry optimization run
qsub run

After completion of the optimization you should extract the final coordinates of the molecule and copy them in the STM directory to compute the KS orbitals and to ocmpute the STM images you can extract the coordinates running the following script:

exercises/2017_ethz_mmm/stm.1495714148.txt.gz · Last modified: 2017/05/25 12:09 by dpasserone