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exercises:2018_ethz_mmm:bands_i_2018 [2018/04/25 09:34]
dpasserone
exercises:2018_ethz_mmm:bands_i_2018 [2018/04/26 10:14] (current)
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>​
  
- 
-<note important>​ 
 ====Task1==== ====Task1====
  
-Construct the primitive cell of the monoclinic phase of HfO2, using ASE and teh information contained in the manuscript +Construct the primitive cell of the monoclinic phase of HfO2, using ASE and teh information contained in the HfO2 manuscript 
-<​note ​warning>Follow the instructions contained in the ASE webpage dedicated to spacegroups+ 
 +<​note ​tip> 
 +Follow the instructions contained in the ASE webpage dedicated to spacegroups
  
 [[https://​wiki.fysik.dtu.dk/​ase/​ase/​spacegroup/​spacegroup.html]] [[https://​wiki.fysik.dtu.dk/​ase/​ase/​spacegroup/​spacegroup.html]]
  
-and find in this article (a pdf copy is included in the tar file of the exercise)+and find in this article (a pdf copy is included in dropbox)
  
 [[https://​journals.aps.org/​prb/​abstract/​10.1103/​PhysRevB.65.233106]] [[https://​journals.aps.org/​prb/​abstract/​10.1103/​PhysRevB.65.233106]]
Line 26: Line 30:
  
 (replace "​..."​) (replace "​..."​)
 +
 +**(comment the line "​hfo2.write("​hfo2.png"​)"​)**
  
 Execution of the python script ​ Execution of the python script ​
Line 33: Line 39:
  
 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>​
  
-<​note ​warning>+<​note ​important>
 -how many atoms are contained in the unit cell? -how many atoms are contained in the unit cell?
  
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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>​
  
  
Line 88: Line 84:
 [[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_2018.1524648882.txt.gz · Last modified: 2018/04/25 09:34 by dpasserone