mirror of
https://github.com/triqs/dft_tools
synced 2024-08-16 17:28:29 +02:00
172 lines
7.4 KiB
ReStructuredText
172 lines
7.4 KiB
ReStructuredText
.. _convWien2k:
|
|
|
|
Interface with Wien2k
|
|
=====================
|
|
|
|
We assume that the user has obtained a self-consistent solution of the
|
|
Kohn-Sham equations. We further have to require that the user is
|
|
familiar with the main in/output files of Wien2k, and how to run
|
|
the DFT code.
|
|
|
|
Conversion for the DMFT self-consistency cycle
|
|
----------------------------------------------
|
|
|
|
First, we have to write the necessary
|
|
quantities into a file that can be processed further by invoking in a
|
|
shell the command
|
|
|
|
`x lapw2 -almd`
|
|
|
|
We note that any other flag for lapw2, such as -c or -so (for
|
|
spin-orbit coupling) has to be added also to this line. This creates
|
|
some files that we need for the Wannier orbital construction.
|
|
|
|
The orbital construction itself is done by the Fortran program
|
|
:program:`dmftproj`. For an extensive manual to this program see
|
|
:download:`TutorialDmftproj.pdf <images_scripts/TutorialDmftproj.pdf>`.
|
|
Here we will only describe the basic steps.
|
|
|
|
In the following, we use SrVO3 as an example to explain the
|
|
input file :file:`case.indmftpr` for :program:`dmftproj`.
|
|
A full tutorial on SrVO3 is available in the :ref:`SrVO3 tutorial <SrVO3>`.
|
|
|
|
.. literalinclude:: ../tutorials/images_scripts/SrVO3.indmftpr
|
|
|
|
The first three lines give the number of inequivalent sites, their
|
|
multiplicity (to be in accordance with the Wien2k *struct* file) and
|
|
the maximum orbital quantum number :math:`l_{max}`. In our case our
|
|
struct file contains the atoms in the order Sr, V, O.
|
|
|
|
Next we have to specify for each of the inequivalent sites, whether
|
|
we want to treat their orbitals as correlated or not. This information
|
|
is given by the following 3 to 5 lines:
|
|
|
|
#. We specify which basis set is used (complex or cubic
|
|
harmonics).
|
|
#. The four numbers refer to *s*, *p*, *d*, and *f* electrons,
|
|
resp. Putting 0 means doing nothing, putting 1 will calculate
|
|
**unnormalized** projectors in compliance with the Wien2k
|
|
definition. The important flag is 2, this means to include these
|
|
electrons as correlated electrons, and calculate normalized Wannier
|
|
functions for them. In the example above, you see that only for the
|
|
vanadium *d* we set the flag to 2. If you want to do simply a DMFT
|
|
calculation, then set everything to 0, except one flag 2 for the
|
|
correlated electrons.
|
|
#. In case you have a irrep splitting of the correlated shell, you can
|
|
specify here how many irreps you have. You see that we put 2, since
|
|
eg and t2g symmetries are irreps in this cubic case. If you don't
|
|
want to use this splitting, just put 0.
|
|
#. (optional) If you specifies a number different from 0 in above line, you have
|
|
to tell now, which of the irreps you want to be treated
|
|
correlated. We want to t2g, and not the eg, so we set 0 for eg and
|
|
1 for t2g. Note that the example above is what you need in 99% of
|
|
the cases when you want to treat only t2g electrons. For eg's only
|
|
(e.g. nickelates), you set 10 and 01 in this line.
|
|
#. (optional) If you have specified a correlated shell for this atom,
|
|
you have to tell if spin-orbit coupling should be taken into
|
|
account. 0 means no, 1 is yes.
|
|
|
|
These lines have to be repeated for each inequivalent atom.
|
|
|
|
The last line gives the energy window, relative to the Fermi energy,
|
|
that is used for the projective Wannier functions. Note that, in
|
|
accordance with Wien2k, we give energies in Rydberg units!
|
|
|
|
After setting up the :file:`case.indmftpr` input file, you run:
|
|
|
|
`dmftproj`
|
|
|
|
Again, adding possible flags like -so for spin-orbit coupling. This
|
|
program produces the following files (in the following, take *case* as
|
|
the standard Wien2k place holder, to be replaced by the actual working
|
|
directory name):
|
|
|
|
* :file:`case.ctqmcout` and :file:`case.symqmc` containing projector
|
|
operators and symmetry operations for orthonormalized Wannier
|
|
orbitals, respectively.
|
|
* :file:`case.parproj` and :file:`case.sympar` containing projector
|
|
operators and symmetry operations for uncorrelated states,
|
|
respectively. These files are needed for projected
|
|
density-of-states or spectral-function calculations in
|
|
post-processing only.
|
|
* :file:`case.oubwin` needed for the charge density recalculation in
|
|
the case of fully self-consistent DFT+DMFT run (see below).
|
|
|
|
Now we convert these files into an hdf5 file that can be used for the
|
|
DMFT calculations. For this purpose we
|
|
use the python module :class:`Wien2kConverter <dft.converters.wien2k_converter.Wien2kConverter>`. It is initialized as::
|
|
|
|
from triqs_dft_tools.converters.wien2k_converter import *
|
|
Converter = Wien2kConverter(filename = case)
|
|
|
|
The only necessary parameter to this construction is the parameter `filename`.
|
|
It has to be the root of the files produces by dmftproj. For our
|
|
example, the :program:`Wien2k` naming convention is that all files have the
|
|
same name, but different extensions, :file:`case.*`. The constructor opens
|
|
an hdf5 archive, named :file:`case.h5`, where all relevant data will be
|
|
stored. For other parameters of the constructor please visit the
|
|
:ref:`refconverters` section of the reference manual.
|
|
|
|
After initializing the interface module, we can now convert the input
|
|
text files to the hdf5 archive by::
|
|
|
|
Converter.convert_dft_input()
|
|
|
|
This reads all the data, and stores it in the file :file:`case.h5`.
|
|
In this step, the files :file:`case.ctqmcout` and
|
|
:file:`case.symqmc` have to be present in the working directory.
|
|
|
|
After this step, all the necessary information for the DMFT loop is
|
|
stored in the hdf5 archive, where the string variable
|
|
`Converter.hdf_filename` gives the file name of the archive.
|
|
|
|
At this point you should use the method :meth:`dos_wannier_basis <dft.sumk_dft_tools.SumkDFTTools.dos_wannier_basis>`
|
|
contained in the module :class:`SumkDFTTools <dft.sumk_dft_tools.SumkDFTTools>` to check the density of
|
|
states of the Wannier orbitals (see :ref:`analysis`).
|
|
|
|
You have now everything for performing a DMFT calculation, and you can
|
|
proceed with the section on :ref:`single-shot DFT+DMFT calculations <singleshot>`.
|
|
|
|
Data for post-processing
|
|
------------------------
|
|
|
|
In case you want to do post-processing of your data using the module
|
|
:class:`SumkDFTTools <dft.sumk_dft_tools.SumkDFTTools>`, some more files
|
|
have to be converted to the hdf5 archive. For instance, for
|
|
calculating the partial density of states or partial charges
|
|
consistent with the definition of :program:`Wien2k`, you have to invoke::
|
|
|
|
Converter.convert_parproj_input()
|
|
|
|
This reads and converts the files :file:`case.parproj` and
|
|
:file:`case.sympar`.
|
|
|
|
If you want to plot band structures, one has to do the
|
|
following. First, one has to do the Wien2k calculation on the given
|
|
:math:`\mathbf{k}`-path, and run :program:`dmftproj` on that path:
|
|
|
|
| `x lapw1 -band`
|
|
| `x lapw2 -band -almd`
|
|
| `dmftproj -band`
|
|
|
|
|
|
Again, maybe with the optional additional extra flags according to
|
|
Wien2k. Now we use a routine of the converter module allows to read
|
|
and convert the input for :class:`SumkDFTTools <dft.sumk_dft_tools.SumkDFTTools>`::
|
|
|
|
Converter.convert_bands_input()
|
|
|
|
After having converted this input, you can further proceed with the
|
|
:ref:`analysis`. For more options on the converter module, please have
|
|
a look at the :ref:`refconverters` section of the reference manual.
|
|
|
|
Data for transport calculations
|
|
-------------------------------
|
|
|
|
For the transport calculations, the situation is a bit more involved,
|
|
since we need also the :program:`optics` package of Wien2k. Please
|
|
look at the section on :ref:`Transport` to see how to do the necessary
|
|
steps, including the conversion.
|
|
|
|
|