mirror of https://gitlab.com/QEF/q-e.git
6148f5e5c5
See https://stackoverflow.com/questions/50148175/what-does-cd-echo-0-sed-s-1-do-in-bash-script Note: some trailing blanks have been removed as well by the script I used. Use "git diff -b" to see only the true changes. |
||
|---|---|---|
| .. | ||
| reference | ||
| README | ||
| run_example | ||
README
In DFT+U, various types of Hubbard projectors can be used.
In this example we show how to generate localized Wannier functions of
the relevant bands around the Fermi energy and use them as Hubbard projectors.
See for instance N.Marzari and D.Vanderbilt, PRB 56, 12847 (1997) and
I. Sousa, N. Marzari, and D.Vanderbilt, PRB 65, 035109 (2001) for the
definition and construction of Maximally Localized Wannier Functions (MLWF).
Although it is possible to generate MLWF using the WANNIER90 package
(www.wannier.org), here we follow a simpler prescription and fix the
phase-factor freedom---intrinsic in any Wannier function determination---
in a sub-optimal but simple way using the atomic wavefunction as a guide.
This is done as a post-processing step with a poormanwannier tool (pmw.x)
that reads atomic wavefunctions and band structure of an DFT calculation
and replaces the atomic wavefunctions with our simple Wannier functions.
The subsequent DFT+U calculation is performed by specifying "HUBBARD {wf}"
so that the freshly produced Wannier functions are used in the projection.
The outcome of this calculation is an insulating state with d-level
occupations really close to 0 or 1.