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exercises:2018_ethz_mmm:bands_i_2018 [2018/04/25 09:37] dpasseroneexercises:2018_ethz_mmm:bands_i_2018 [2018/04/26 10:13] dpasserone
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 of HfO2 to form silicates played a key role in the industrial transition. of HfO2 to form silicates played a key role in the industrial transition.
  
 +<note importat> 
 +please download 
 + **hfo2.py, PhysRevB...pdf, bands_si.py, bands_cu.py** from [[https://polybox.ethz.ch/index.php/s/CH5VdcI40YdELez|this link]]  
 +</note>
  
 ====Task1==== ====Task1====
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 (replace "...") (replace "...")
 +
 +(comment the line "hfo2.write("hfo2.png")")
  
 Execution of the python script  Execution of the python script 
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 will open the ASE visualizer showing you the structure, will open the ASE visualizer showing you the structure,
-will produce the file hfo2.xyz, hfo2.png and hfo2.pov +will produce the file hfo2.xyz, hfo2.png 
- +
-to create a "nice" image of the primitive cell you can render the output file hfo2.pov with the command +
-<code> +
-povray +W320 +H320 -I./hfo2.pov -Ohfo2 +P +X +A +FJ +C +
-</code> +
-or executing the script +
-<code> +
-./povray.sc  +
-</code> +
-(that will take care of removing files hfo2.jpg and hfo2.inc)+
 </note> </note>
  
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 ====Task2==== ====Task2====
 Have a look at the atomic coordinates, for example in the file hfo2.xyz (where you also find the cell vectors in cartesian coordinates) and  Have a look at the atomic coordinates, for example in the file hfo2.xyz (where you also find the cell vectors in cartesian coordinates) and 
-<note warning>+<note important>
 try to reproduce them (just the 4 Hf atoms), starting from the try to reproduce them (just the 4 Hf atoms), starting from the
 coordinates that you find in the article and applying the symmetry operations of the space group: coordinates that you find in the article and applying the symmetry operations of the space group:
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 4)x,-y+1/2,z+1/2 4)x,-y+1/2,z+1/2
 +<note tip>
 **DO NOT FORGET Periodic Boundary Conditions!!** but it's simple: x,y,z are given in crystal coordinates so, if for example x=0.276 **DO NOT FORGET Periodic Boundary Conditions!!** but it's simple: x,y,z are given in crystal coordinates so, if for example x=0.276
 for "-x" you can use -x+1 = 0.724 for "-x" you can use -x+1 = 0.724
  
-</note> +
-<note important>+
 usually the coordinates are provided in crystal coordinates so usually the coordinates are provided in crystal coordinates so
-if a1=(a1x,a1y,a1z),a2=(a2x,a2y,a2z),a3=(a3x,a3y,a3z) are the three basis vectors of the crystalin cartesian coordinates +if a1=(a1x,a1y,a1z),a2=(a2x,a2y,a2z),a3=(a3x,a3y,a3z) are the three basis vectors of the crystal in cartesian coordinates 
-and (x1,y1,z1) will be the crystal coordinates of atom 1, the cartessian coordinates of atom 1 will be:+and (x1,y1,z1)  the crystal coordinates of atom 1, the cartesian coordinates of atom 1 will be:
 x1*a1 + x2*a2 + x3*a3 x1*a1 + x2*a2 + x3*a3
 </note> </note>
 +</note> 
 +<note important>obtain teh HfO2 structure from [[https://materialsproject.org/]]</note>
  
 ====Task 3==== ====Task 3====
 Check the lecture notes for the free electron model and: Check the lecture notes for the free electron model and:
-<note warning>Compute the Fermi energy (in eV) and the Fermi wavevector (in cm-1) for Cu,Au,Ag </note>+<note important>Compute the Fermi energy (in eV) and the Fermi wavevector (in cm-1) for Cu,Au,Ag </note>
  
  
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 [[https://wiki.fysik.dtu.dk/ase/ase/dft/kpoints.html]] [[https://wiki.fysik.dtu.dk/ase/ase/dft/kpoints.html]]
  
-<note warning>+<note important>
 Compute the free electron bandstructure of Si and Cu Compute the free electron bandstructure of Si and Cu
-(Have a look at the scripts included in the exercise directory) 
- 
 Write the CARTESIAN COORDINATES of the Gamma, X, W points of FCC Write the CARTESIAN COORDINATES of the Gamma, X, W points of FCC
 +<note tip>
 +Have a look at the scripts included in the exercise directory
 +
 +</note>
 +<note warning>How does the Fermi energy that you computed for Cu compares with the one plotted in the bands?</note>
 </note> </note>
exercises/2018_ethz_mmm/bands_i_2018.txt · Last modified: 2020/08/21 10:15 by 127.0.0.1