This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
|
graphene:electronic_structure [2010/02/27 11:21] jelen |
graphene:electronic_structure [2011/02/18 13:13] (current) |
||
|---|---|---|---|
| Line 1: | Line 1: | ||
| + | ====== Band structure plot ====== | ||
| + | |||
| In previous section we optimized the lattice parameter of graphene. In this section we show how to generate the band structure at given high-symmetry directions. We follow the same procedure as in the previous case of the Silicon bulk: | In previous section we optimized the lattice parameter of graphene. In this section we show how to generate the band structure at given high-symmetry directions. We follow the same procedure as in the previous case of the Silicon bulk: | ||
| - | ====== 1. run 1 SCF to obtain the SCF charges ====== | + | === Procedure === |
| - | + | ||
| - | ===== 2. fix SCF charges and use a set special high symmetry k-points ===== | + | |
| - | ==== 3. run ==== | + | - obtain the SCF charges |
| - | + | - generate a set of special high symmetry k-points | |
| + | - get eigenvalue spectra with fixed SCF charges & the set of high symmetry k-points | ||
| + | - plot eigenvalue vs. k-points | ||
| + | | ||
| To plot the band structure we generated a set of the special k-points heading from K(1/√3,1/3) point to Γ(0,0) ending at M(0,2/3) stored in file C1.kgm.kpts. | To plot the band structure we generated a set of the special k-points heading from K(1/√3,1/3) point to Γ(0,0) ending at M(0,2/3) stored in file C1.kgm.kpts. | ||
| + | |||
| + | |||
| + | ====== Real space electron denisty ====== | ||
| + | |||
| + | Another way to analyze the electronic structure of material is a plot of electron density in real space. This kind of analysis can be compared, with certain caution, with STM images. To obtain this image we have to proceed following steps: | ||
| + | |||
| + | - obtain the SCF charges | ||
| + | - plot wavefunction in real-space | ||