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exercises:2017_ethz_mmm:stm

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exercises:2017_ethz_mmm:stm [2017/05/25 12:17] – dpasseroneexercises:2017_ethz_mmm:stm [2020/08/21 10:15] (current) – external edit 127.0.0.1
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 thus we have a disceret spectrum of energies and it is quite likely that for  values of the bias voltage thus we have a disceret spectrum of energies and it is quite likely that for  values of the bias voltage
 that fall in the HOMO-LUMO gap we will obtain an empty image that fall in the HOMO-LUMO gap we will obtain an empty image
 +
 +Now we can simulate for teh same ribbon a AFM image:
 +Go the the AFM directory of TASK_1
 +copy there the p.xyz file that you find in the STM directory
 +and execute:
 +
 +<code>
 +./run_PP
 +</code>
 +It will take ~ 5 minutes, then you will find a dir containing the AFM simulated image.
 +
 +===TASK_2===
 +Repeat all the instructions of TASK_1 for the scripts present in the dir TASK_2
 +<note warning>
 +Be carefulhere we do a spin polarized simulation,
 +we have to distinguish the three C atoms of one terminus of the ribbon from the 
 +three of the opposite terminus calling them C1 and C2.
 +
 +When the file p.xyz is created in the STM dir (after running ./pos.sc)
 +copy it immediateli to the AFM dir.
 +Now, before executing the instructions for the STM dir
 +edit the file p.xyz and modify it in such a way that
 +the first three C atoms will be labelled as C1
 +and the C atoms from 4 to 6 will be labelled as C2
 +<code>
 +222
 +   
 +  C1        6.0848407282        7.8280098155       21.6125989354
 +  C1        6.0865671686       12.7633436664       21.6071222309
 +  C1        6.1020007836       10.2957686990       21.6036624306
 +  C2       56.3447906713       10.2958157091       21.6033852713
 +  C2       56.3619529363        7.8280149623       21.6128774460
 +  C2       56.3601930737       12.7634261117       21.6063533886
 +  H         4.9837063610        7.8327959357       21.5912164696
 +  H         4.9855872642       12.7623732365       21.5844580428
 +</code>
 +
 +</note>
 +
 +<note important>
 +Notice the difference between the images in TASK_2 and the images in TASK_1
 +In TASK_2 we have KS states localised at the termini of the ribbon.
 +These states are suppressed by the addiitonal H atoms in TASK_1
 +</note>
  
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