====== Calculation of surface energies of Au ======

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Take the above table as reference for the orders of magnitude of surface energies. 
You can download the ** commented **  inputs by downloading from the wiki: {{exercise_3.2.zip|exercise_3.2.zip}}) the necessary files for computing the surface energies of all 3 high symmetry faces of gold.
In principle all reconstructed phases should be with a lower surface energy, but this EAM potential fails for some of them.
The input files are:
  - 100_bulk.inp for determining the energy per atom in the bulk
  - 100_unr.inp for the bulk termination (100)
  - 100_rec.inp for the hexagonally reconstructed (100)
  - 110_unr.inp for the (110) bulk termination
  - 110_rec.inp for the (2x1) reconstruction
  - 111.inp for the unreconstructed (111).

The compute_surf scripts give an idea how to compute the surface energies.
Assignments:

  - Mark surface energies and relaxations of the first 2-3 top layers (use vmd or editor)
  - Try to color the surfaces in vmd in a way that makes the height evident (ask the assistant) and produce snapshots (render)
  - Comment on the (2x1) reconstruction: what do you see?
  - Plot the same, but adding periodic images in vmd: remember pbc set { a b c 90 90 90 }.

<note tip>Hint: you can save a configuration file in vmd and reuse it for a new sample! Ask the assistant!</note>