mirror of https://gitlab.com/QEF/q-e.git
41 lines
1.7 KiB
Plaintext
41 lines
1.7 KiB
Plaintext
|
|
This example shows how to use pw.x and pwcond.x to compute the complex band
|
|
structure (CBS) and transmittance within DFT+U for an Au monatomic chain with
|
|
a CO impurity. The Hubbard potential is included in the coefficients of the
|
|
non-local part of the pseudopotential (PP), as described in:
|
|
G. Sclauzero, A. Dal Corso, Phys. Rev. B 87, 085108 (2013)
|
|
|
|
The plain LDA result is compared with the LDA+U result (using U=3 eV),
|
|
therefore the following calculations are performed first without, and
|
|
then with the Hubbard U potential.
|
|
|
|
|
|
1.) Visualization of the CBS:
|
|
|
|
a) A pw.x calculation provides the self-consistent potential for a perfect
|
|
Au monatomic chain (1 atom per cell).
|
|
|
|
b) A pwcond.x calculation gives for every energy in the chosen range the CBS
|
|
of the Au chain. Notice how the 5d-states of Au are pushed away from the
|
|
Fermi energy by the Hubbard U potential.
|
|
|
|
|
|
2.) Calculation of the transmittance through the chain with the impurity:
|
|
|
|
a) Two pw.x calculations provide the self-consistent potentials for a perfect
|
|
Au chain (used as left and right lead) and for a Au chain (6 atoms long)
|
|
with a CO molecule adsorbed atop the central Au atom (scattering region).
|
|
|
|
b) A pwcond.x calculation gives the transmittance through the Au chain with
|
|
the adsorbed impurity for selected energies around the Fermi level.
|
|
|
|
|
|
You can plot the results with Gnuplot using the automatically generated script.
|
|
|
|
|
|
N.B.: 1. In order to make the tests faster, these calculations are not fully
|
|
converged with respect to k points, cut-off and size of the cell.
|
|
2. The PP must contain the AE wavefunctions for the valence orbitals
|
|
that are included in the Hubbard term (e.g. using lsave_wfc=.true.
|
|
when generating the PP through ld1.x).
|