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(doc) New structure for the converter tools doc
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aichhorn
Manuel
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117
doc/guide/conv_W90.rst
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doc/guide/conv_W90.rst
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.. _convW90:
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Wannier90 Converter
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===================
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Using this converter it is possible to convert the output of
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`wannier90 <http://wannier.org>`_
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Maximally Localized Wannier Functions (MLWF) and create a HDF5 archive
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suitable for one-shot DMFT calculations with the
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:class:`SumkDFT <dft.sumk_dft.SumkDFT>` class.
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The user must supply two files in order to run the Wannier90 Converter:
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#. The file :file:`seedname_hr.dat`, which contains the DFT Hamiltonian
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in the MLWF basis calculated through :program:`wannier90` with ``hr_plot = true``
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(please refer to the :program:`wannier90` documentation).
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#. A file named :file:`seedname.inp`, which contains the required
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information about the :math:`\mathbf{k}`-point mesh, the electron density,
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the correlated shell structure, ... (see below).
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Here and in the following, the keyword ``seedname`` should always be intended
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as a placeholder for the actual prefix chosen by the user when creating the
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input for :program:`wannier90`.
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Once these two files are available, one can use the converter as follows::
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from triqs_dft_tools.converters import Wannier90Converter
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Converter = Wannier90Converter(seedname='seedname')
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Converter.convert_dft_input()
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The converter input :file:`seedname.inp` is a simple text file with
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the following format (do not use the text/comments in your input file):
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.. literalinclude:: images_scripts/LaVO3_w90.inp
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The example shows the input for the perovskite crystal of LaVO\ :sub:`3`
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in the room-temperature `Pnma` symmetry. The unit cell contains four
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symmetry-equivalent correlated sites (the V atoms) and the total number
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of electrons per unit cell is 8 (see second line).
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The first line specifies how to generate the :math:`\mathbf{k}`-point
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mesh that will be used to obtain :math:`H(\mathbf{k})`
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by Fourier transforming :math:`H(\mathbf{R})`.
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Currently implemented options are:
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* :math:`\Gamma`-centered uniform grid with dimensions
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:math:`n_{k_x} \times n_{k_y} \times n_{k_z}`;
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specify ``0`` followed by the three grid dimensions,
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like in the example above
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* :math:`\Gamma`-centered uniform grid with dimensions
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automatically determined by the converter (from the number of
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:math:`\mathbf{R}` vectors found in :file:`seedname_hr.dat`);
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just specify ``-1``
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Inside :file:`seedname.inp`, it is crucial to correctly specify the
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correlated shell structure, which depends on the contents of the
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:program:`wannier90` output :file:`seedname_hr.dat` and on the order
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of the MLWFs contained in it. In this example we have four lines for the
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four V atoms. The MLWFs were constructed for the t\ :sub:`2g` subspace, and thus
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we set ``l`` to 2 and ``dim`` to 3 for all V atoms. Further the spin-orbit coupling (``SO``)
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is set to 0 and ``irep`` to 0.
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As in this example all 4 V atoms are equivalent we set ``sort`` to 0. We note
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that, e.g., for a magnetic DMFT calculation the correlated atoms can be made
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inequivalent at this point by using different values for ``sort``.
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The number of MLWFs must be equal to, or greater than the total number
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of correlated orbitals (i.e., the sum of all ``dim`` in :file:`seedname.inp`).
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If the converter finds fewer MLWFs inside :file:`seedname_hr.dat`, then it
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stops with an error; if it finds more MLWFs, then it assumes that the
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additional MLWFs correspond to uncorrelated orbitals (e.g., the O-\ `2p` shells).
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When reading the hoppings :math:`\langle w_i | H(\mathbf{R}) | w_j \rangle`
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(where :math:`w_i` is the :math:`i`-th MLWF), the converter also assumes that
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the first indices correspond to the correlated shells (in our example,
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the V-t\ :sub:`2g` shells). Therefore, the MLWFs corresponding to the
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uncorrelated shells (if present) must be listed **after** those of the
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correlated shells.
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With the :program:`wannier90` code, this can be achieved by listing the
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projections for the uncorrelated shells after those for the correlated shells.
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In our `Pnma`-LaVO\ :sub:`3` example, for instance, we could use::
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Begin Projections
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V:l=2,mr=2,3,5:z=0,0,1:x=-1,1,0
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O:l=1:mr=1,2,3:z=0,0,1:x=-1,1,0
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End Projections
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where the ``x=-1,1,0`` option indicates that the V--O bonds in the octahedra are
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rotated by (approximatively) 45 degrees with respect to the axes of the `Pbnm` cell.
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The converter will analyse the matrix elements of the local Hamiltonian
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to find the symmetry matrices `rot_mat` needed for the global-to-local
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transformation of the basis set for correlated orbitals
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(see section :ref:`hdfstructure`).
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The matrices are obtained by finding the unitary transformations that diagonalize
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:math:`\langle w_i | H_I(\mathbf{R}=0,0,0) | w_j \rangle`, where :math:`I` runs
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over the correlated shells and `i,j` belong to the same shell (more details elsewhere...).
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If two correlated shells are defined as equivalent in :file:`seedname.inp`,
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then the corresponding eigenvalues have to match within a threshold of 10\ :sup:`-5`,
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otherwise the converter will produce an error/warning.
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If this happens, please carefully check your data in :file:`seedname_hr.dat`.
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This method might fail in non-trivial cases (i.e., more than one correlated
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shell is present) when there are some degenerate eigenvalues:
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so far tests have not shown any issue, but one must be careful in those cases
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(the converter will print a warning message).
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The current implementation of the Wannier90 Converter has some limitations:
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* Since :program:`wannier90` does not make use of symmetries (symmetry-reduction
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of the :math:`\mathbf{k}`-point grid is not possible), the converter always
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sets ``symm_op=0`` (see the :ref:`hdfstructure` section).
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* No charge self-consistency possible at the moment.
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* Calculations with spin-orbit (``SO=1``) are not supported.
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* The spin-polarized case (``SP=1``) is not yet tested.
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* The post-processing routines in the module
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:class:`SumkDFTTools <dft.sumk_dft_tools.SumkDFTTools>`
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were not tested with this converter.
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* ``proj_mat_all`` are not used, so there are no projectors onto the
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uncorrelated orbitals for now.
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100
doc/guide/conv_generalhk.rst
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100
doc/guide/conv_generalhk.rst
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.. _convgeneralhk:
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A general H(k)
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==============
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In addition to the more extensive Wien2k, VASP, and W90 converters,
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:program:`DFTTools` contains also a light converter. It takes only
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one inputfile, and creates the necessary hdf outputfile for
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the DMFT calculation. The header of this input file has a defined
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format, an example is the following (do not use the text/comments in your
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input file):
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.. literalinclude:: images_scripts/case.hk
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The lines of this header define
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#. Number of :math:`\mathbf{k}`-points used in the calculation
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#. Electron density for setting the chemical potential
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#. Number of total atomic shells in the hamiltonian matrix. In short,
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this gives the number of lines described in the following. IN the
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example file give above this number is 2.
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#. The next line(s) contain four numbers each: index of the atom, index
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of the equivalent shell, :math:`l` quantum number, dimension
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of this shell. Repeat this line for each atomic shell, the number
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of the shells is given in the previous line.
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In the example input file given above, we have two inequivalent
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atomic shells, one on atom number 1 with a full d-shell (dimension 5),
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and one on atom number 2 with one p-shell (dimension 3).
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Other examples for these lines are:
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#. Full d-shell in a material with only one correlated atom in the
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unit cell (e.g. SrVO3). One line is sufficient and the numbers
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are `1 1 2 5`.
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#. Full d-shell in a material with two equivalent atoms in the unit
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cell (e.g. FeSe): You need two lines, one for each equivalent
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atom. First line is `1 1 2 5`, and the second line is
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`2 1 2 5`. The only difference is the first number, which tells on
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which atom the shell is located. The second number is the
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same in both lines, meaning that both atoms are equivalent.
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#. t2g orbitals on two non-equivalent atoms in the unit cell: Two
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lines again. First line is `1 1 2 3`, second line `2 2 2 3`. The
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difference to the case above is that now also the second number
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differs. Therefore, the two shells are treated independently in
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the calculation.
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#. d-p Hamiltonian in a system with two equivalent atoms each in
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the unit cell (e.g. FeSe has two Fe and two Se in the unit
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cell). You need for lines. First line `1 1 2 5`, second
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line
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`2 1 2 5`. These two lines specify Fe as in the case above. For the p
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orbitals you need line three as `3 2 1 3` and line four
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as `4 2 1 3`. We have 4 atoms, since the first number runs from 1 to 4,
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but only two inequivalent atoms, since the second number runs
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only form 1 to 2.
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Note that the total dimension of the hamiltonian matrices that are
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read in is the sum of all shell dimensions that you specified. For
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example number 4 given above we have a dimension of 5+5+3+3=16. It is important
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that the order of the shells that you give here must be the same as
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the order of the orbitals in the hamiltonian matrix. In the last
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example case above the code assumes that matrix index 1 to 5
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belongs to the first d shell, 6 to 10 to the second, 11 to 13 to
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the first p shell, and 14 to 16 the second p shell.
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#. Number of correlated shells in the hamiltonian matrix, in the same
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spirit as line 3.
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#. The next line(s) contain six numbers: index of the atom, index
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of the equivalent shell, :math:`l` quantum number, dimension
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of the correlated shells, a spin-orbit parameter, and another
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parameter defining interactions. Note that the latter two
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parameters are not used at the moment in the code, and only kept
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for compatibility reasons. In our example file we use only the
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d-shell as correlated, that is why we have only one line here.
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#. The last line contains several numbers: the number of irreducible
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representations, and then the dimensions of the irreps. One
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possibility is as the example above, another one would be 2
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2 3. This would mean, 2 irreps (eg and t2g), of dimension 2 and 3,
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resp.
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After these header lines, the file has to contain the Hamiltonian
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matrix in orbital space. The standard convention is that you give for
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each :math:`\mathbf{k}`-point first the matrix of the real part, then the
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matrix of the imaginary part, and then move on to the next :math:`\mathbf{k}`-point.
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The converter itself is used as::
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from triqs_dft_tools.converters.hk_converter import *
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Converter = HkConverter(filename = hkinputfile)
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Converter.convert_dft_input()
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where :file:`hkinputfile` is the name of the input file described
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above. This produces the hdf file that you need for a DMFT calculation.
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For more options of this converter, have a look at the
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:ref:`refconverters` section of the reference manual.
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141
doc/guide/conv_vasp.rst
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doc/guide/conv_vasp.rst
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.. _convVASP:
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Interface with VASP
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===================
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.. warning::
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The VASP interface is in the alpha-version and the VASP part of it is not
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yet publicly released. The documentation may, thus, be subject to changes
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before the final release.
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*Limitations of the alpha-version:*
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* The interface works correctly only if the k-point symmetries
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are turned off during the VASP run (ISYM=-1).
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* Generation of projectors for k-point lines (option `Lines` in KPOINTS)
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needed for Bloch spectral function calculations is not possible at the moment.
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* The interface currently supports only collinear-magnetism calculation
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(this implis no spin-orbit coupling) and
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spin-polarized projectors have not been tested.
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A detailed description of the VASP converter tool PLOVasp can be found
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in :ref:`plovasp`. Here, a quick-start guide is presented.
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The VASP interface relies on new options introduced since version
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5.4.x. In particular, a new INCAR-option `LOCPROJ`
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and new `LORBIT` modes 13 and 14 have been added.
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Option `LOCPROJ` selects a set of localized projectors that will
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be written to file `LOCPROJ` after a successful VASP run.
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A projector set is specified by site indices,
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labels of the target local states, and projector type:
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| `LOCPROJ = <sites> : <shells> : <projector type>`
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where `<sites>` represents a list of site indices separated by spaces,
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with the indices corresponding to the site position in the POSCAR file;
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`<shells>` specifies local states (see below);
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`<projector type>` chooses a particular type of the local basis function.
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The recommended projector type is `Pr 2`.
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The allowed labels of the local states defined in terms of cubic
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harmonics are:
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* Entire shells: `s`, `p`, `d`, `f`
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* `p`-states: `py`, `pz`, `px`
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* `d`-states: `dxy`, `dyz`, `dz2`, `dxz`, `dx2-y2`
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* `f`-states: `fy(3x2-y2)`, `fxyz`, `fyz2`, `fz3`,
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`fxz2`, `fz(x2-y2)`, `fx(x2-3y2)`.
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For projector type `Pr 2`, one should also set `LORBIT = 14` in INCAR
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and provide parameters `EMIN`, `EMAX` which, in this case, define an
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energy range (window) corresponding to the valence states. Note that as in the case
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of DOS calculation the position of the valence states depends on the
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Fermi level.
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For example, in case of SrVO3 one may first want to perform a self-consistent
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calculation, then set `ICHARGE = 1` and add the following additional
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lines into INCAR (provided that V is the second ion in POSCAR):
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| `EMIN = 3.0`
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| `EMAX = 8.0`
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| `LORBIT = 14`
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| `LOCPROJ = 2 : d : Pr 2`
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The energy range does not have to be precise. Important is that it has a large
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overlap with valence bands and no overlap with semi-core or high unoccupied states.
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Conversion for the DMFT self-consistency cycle
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----------------------------------------------
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The projectors generated by VASP require certain post-processing before
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they can be used for DMFT calculations. The most important step is to normalize
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them within an energy window that selects band states relevant for the impurity
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problem. Note that this energy window is different from the one described above
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and it must be chosen independently of the energy
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range given by `EMIN, EMAX` in INCAR.
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Post-processing of `LOCPROJ` data is generally done as follows:
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#. Prepare an input file `<name>.cfg` (e.g., `plo.cfg`) that describes the definition
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of your impurity problem (more details below).
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#. Extract the value of the Fermi level from OUTCAR and paste at the end of
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the first line of LOCPROJ.
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#. Run :program:`plovasp` with the input file as an argument, e.g.:
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| `plovasp plo.cfg`
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This requires that the TRIQS paths are set correctly (see Installation
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of TRIQS).
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If everything goes right one gets files `<name>.ctrl` and `<name>.pg1`.
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These files are needed for the converter that will be invoked in your
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DMFT script.
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The format of input file `<name>.cfg` is described in details in
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:ref:`plovasp`. Here we just give a simple example for the case
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of SrVO3:
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.. literalinclude:: images_scripts/srvo3.cfg
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A projector shell is defined by a section `[Shell 1]` where the number
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can be arbitrary and used only for user convenience. Several
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parameters are required
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- **IONS**: list of site indices which must be a subset of indices
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given earlier in `LOCPROJ`.
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- **LSHELL**: :math:`l`-quantum number of the projector shell; the corresponding
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orbitals must be present in `LOCPROJ`.
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- **EWINDOW**: energy window in which the projectors are normalized;
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note that the energies are defined with respect to the Fermi level.
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Option **TRANSFORM** is optional but here it is specified to extract
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only three :math:`t_{2g}` orbitals out of five `d` orbitals given by
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:math:`l = 2`.
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The conversion to a h5-file is performed in the same way as for Wien2TRIQS::
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from triqs_dft_tools.converters.vasp_converter import *
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Converter = VaspConverter(filename = filename)
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Converter.convert_dft_input()
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As usual, the resulting h5-file can then be used with the SumkDFT class.
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Note that the automatic detection of the correct block structure might
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fail for VASP inputs.
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This can be circumvented by setting a bigger value of the threshold in
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:class:`SumkDFT <dft.sumk_dft.SumkDFT>`, e.g.::
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SK.analyse_block_structure(threshold = 1e-4)
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However, do this only after a careful study of the density matrix and
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the projected DOS in the localized basis.
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174
doc/guide/conv_wien2k.rst
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174
doc/guide/conv_wien2k.rst
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.. _convWien2k:
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Interface with Wien2k
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=====================
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We assume that the user has obtained a self-consistent solution of the
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Kohn-Sham equations. We further have to require that the user is
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familiar with the main in/output files of Wien2k, and how to run
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the DFT code.
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Conversion for the DMFT self-consistency cycle
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----------------------------------------------
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First, we have to write the necessary
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quantities into a file that can be processed further by invoking in a
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shell the command
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`x lapw2 -almd`
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We note that any other flag for lapw2, such as -c or -so (for
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spin-orbit coupling) has to be added also to this line. This creates
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some files that we need for the Wannier orbital construction.
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The orbital construction itself is done by the Fortran program
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:program:`dmftproj`. For an extensive manual to this program see
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:download:`TutorialDmftproj.pdf <images_scripts/TutorialDmftproj.pdf>`.
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Here we will only describe the basic steps.
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Let us take the compound SrVO3, a commonly used
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example for DFT+DMFT calculations. The input file for
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:program:`dmftproj` looks like
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||||
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.. literalinclude:: images_scripts/SrVO3.indmftpr
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The first three lines give the number of inequivalent sites, their
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multiplicity (to be in accordance with the Wien2k *struct* file) and
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the maximum orbital quantum number :math:`l_{max}`. In our case our
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struct file contains the atoms in the order Sr, V, O.
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Next we have to
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specify for each of the inequivalent sites, whether we want to treat
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their orbitals as correlated or not. This information is given by the
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following 3 to 5 lines:
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#. 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 this 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 are
|
||||
called the same, for instance
|
||||
:file:`SrVO3.*`, so you would give `filename = "SrVO3"`. The constructor opens
|
||||
an hdf5 archive, named :file:`case.h5`, where all the data is
|
||||
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.
|
||||
|
||||
|
||||
@ -1,539 +1,26 @@
|
||||
.. _conversion:
|
||||
|
||||
Orbital construction and conversion
|
||||
===================================
|
||||
Supported interfaces
|
||||
====================
|
||||
|
||||
The first step for a DMFT calculation is to provide the necessary
|
||||
input based on a DFT calculation. We will not review how to do the DFT
|
||||
calculation here in this documentation, but refer the user to the
|
||||
documentation and tutorials that come with the actual DFT
|
||||
package. Here, we will describe how to use output created by Wien2k,
|
||||
as well as how to use the light-weight general interface.
|
||||
|
||||
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.
|
||||
|
||||
Let us take the compound SrVO3, a commonly used
|
||||
example for DFT+DMFT calculations. The input file for
|
||||
:program:`dmftproj` looks like
|
||||
|
||||
.. literalinclude:: 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 this 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 Wien2k naming convention is that all files are
|
||||
called the same, for instance
|
||||
:file:`SrVO3.*`, so you would give `filename = "SrVO3"`. The constructor opens
|
||||
an hdf5 archive, named :file:`case.h5`, where all the data is
|
||||
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 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.
|
||||
|
||||
Interface with VASP
|
||||
---------------------
|
||||
|
||||
.. warning::
|
||||
The VASP interface is in the alpha-version and the VASP part of it is not
|
||||
yet publicly released. The documentation may, thus, be subject to changes
|
||||
before the final release.
|
||||
|
||||
*Limitations of the alpha-version:*
|
||||
|
||||
* The interface works correctly only if the k-point symmetries
|
||||
are turned off during the VASP run (ISYM=-1).
|
||||
|
||||
* Generation of projectors for k-point lines (option `Lines` in KPOINTS)
|
||||
needed for Bloch spectral function calculations is not possible at the moment.
|
||||
|
||||
* The interface currently supports only collinear-magnetism calculation
|
||||
(this implis no spin-orbit coupling) and
|
||||
spin-polarized projectors have not been tested.
|
||||
|
||||
A detailed description of the VASP converter tool PLOVasp can be found
|
||||
in :ref:`plovasp`. Here, a quick-start guide is presented.
|
||||
|
||||
The VASP interface relies on new options introduced since version
|
||||
5.4.x. In particular, a new INCAR-option `LOCPROJ`
|
||||
and new `LORBIT` modes 13 and 14 have been added.
|
||||
|
||||
Option `LOCPROJ` selects a set of localized projectors that will
|
||||
be written to file `LOCPROJ` after a successful VASP run.
|
||||
A projector set is specified by site indices,
|
||||
labels of the target local states, and projector type:
|
||||
|
||||
| `LOCPROJ = <sites> : <shells> : <projector type>`
|
||||
|
||||
where `<sites>` represents a list of site indices separated by spaces,
|
||||
with the indices corresponding to the site position in the POSCAR file;
|
||||
`<shells>` specifies local states (see below);
|
||||
`<projector type>` chooses a particular type of the local basis function.
|
||||
The recommended projector type is `Pr 2`.
|
||||
|
||||
The allowed labels of the local states defined in terms of cubic
|
||||
harmonics are:
|
||||
|
||||
* Entire shells: `s`, `p`, `d`, `f`
|
||||
|
||||
* `p`-states: `py`, `pz`, `px`
|
||||
|
||||
* `d`-states: `dxy`, `dyz`, `dz2`, `dxz`, `dx2-y2`
|
||||
|
||||
* `f`-states: `fy(3x2-y2)`, `fxyz`, `fyz2`, `fz3`,
|
||||
`fxz2`, `fz(x2-y2)`, `fx(x2-3y2)`.
|
||||
|
||||
For projector type `Pr 2`, one should also set `LORBIT = 14` in INCAR
|
||||
and provide parameters `EMIN`, `EMAX` which, in this case, define an
|
||||
energy range (window) corresponding to the valence states. Note that as in the case
|
||||
of DOS calculation the position of the valence states depends on the
|
||||
Fermi level.
|
||||
|
||||
For example, in case of SrVO3 one may first want to perform a self-consistent
|
||||
calculation, then set `ICHARGE = 1` and add the following additional
|
||||
lines into INCAR (provided that V is the second ion in POSCAR):
|
||||
|
||||
| `EMIN = 3.0`
|
||||
| `EMAX = 8.0`
|
||||
| `LORBIT = 14`
|
||||
| `LOCPROJ = 2 : d : Pr 2`
|
||||
|
||||
The energy range does not have to be precise. Important is that it has a large
|
||||
overlap with valence bands and no overlap with semi-core or high unoccupied states.
|
||||
|
||||
Conversion for the DMFT self-consistency cycle
|
||||
""""""""""""""""""""""""""""""""""""""""""""""
|
||||
|
||||
The projectors generated by VASP require certain post-processing before
|
||||
they can be used for DMFT calculations. The most important step is to normalize
|
||||
them within an energy window that selects band states relevant for the impurity
|
||||
problem. Note that this energy window is different from the one described above
|
||||
and it must be chosen independently of the energy
|
||||
range given by `EMIN, EMAX` in INCAR.
|
||||
|
||||
Post-processing of `LOCPROJ` data is generally done as follows:
|
||||
|
||||
#. Prepare an input file `<name>.cfg` (e.g., `plo.cfg`) that describes the definition
|
||||
of your impurity problem (more details below).
|
||||
|
||||
#. Extract the value of the Fermi level from OUTCAR and paste at the end of
|
||||
the first line of LOCPROJ.
|
||||
|
||||
#. Run :program:`plovasp` with the input file as an argument, e.g.:
|
||||
|
||||
| `plovasp plo.cfg`
|
||||
|
||||
This requires that the TRIQS paths are set correctly (see Installation
|
||||
of TRIQS).
|
||||
|
||||
If everything goes right one gets files `<name>.ctrl` and `<name>.pg1`.
|
||||
These files are needed for the converter that will be invoked in your
|
||||
DMFT script.
|
||||
|
||||
The format of input file `<name>.cfg` is described in details in
|
||||
:ref:`plovasp`. Here we just give a simple example for the case
|
||||
of SrVO3:
|
||||
|
||||
.. literalinclude:: images_scripts/srvo3.cfg
|
||||
|
||||
A projector shell is defined by a section `[Shell 1]` where the number
|
||||
can be arbitrary and used only for user convenience. Several
|
||||
parameters are required
|
||||
|
||||
- **IONS**: list of site indices which must be a subset of indices
|
||||
given earlier in `LOCPROJ`.
|
||||
- **LSHELL**: :math:`l`-quantum number of the projector shell; the corresponding
|
||||
orbitals must be present in `LOCPROJ`.
|
||||
- **EWINDOW**: energy window in which the projectors are normalized;
|
||||
note that the energies are defined with respect to the Fermi level.
|
||||
|
||||
Option **TRANSFORM** is optional but here it is specified to extract
|
||||
only three :math:`t_{2g}` orbitals out of five `d` orbitals given by
|
||||
:math:`l = 2`.
|
||||
|
||||
The conversion to a h5-file is performed in the same way as for Wien2TRIQS::
|
||||
|
||||
from triqs_dft_tools.converters.vasp_converter import *
|
||||
Converter = VaspConverter(filename = filename)
|
||||
Converter.convert_dft_input()
|
||||
|
||||
As usual, the resulting h5-file can then be used with the SumkDFT class.
|
||||
|
||||
Note that the automatic detection of the correct block structure might
|
||||
fail for VASP inputs.
|
||||
This can be circumvented by setting a bigger value of the threshold in
|
||||
:class:`SumkDFT <dft.sumk_dft.SumkDFT>`, e.g.::
|
||||
|
||||
SK.analyse_block_structure(threshold = 1e-4)
|
||||
|
||||
However, do this only after a careful study of the density matrix and
|
||||
the projected DOS in the localized basis.
|
||||
|
||||
A general H(k)
|
||||
--------------
|
||||
|
||||
In addition to the more complicated Wien2k converter,
|
||||
:program:`DFTTools` contains also a light converter. It takes only
|
||||
one inputfile, and creates the necessary hdf outputfile for
|
||||
the DMFT calculation. The header of this input file has a defined
|
||||
format, an example is the following (do not use the text/comments in your
|
||||
input file):
|
||||
|
||||
.. literalinclude:: images_scripts/case.hk
|
||||
|
||||
The lines of this header define
|
||||
|
||||
#. Number of :math:`\mathbf{k}`-points used in the calculation
|
||||
#. Electron density for setting the chemical potential
|
||||
#. Number of total atomic shells in the hamiltonian matrix. In short,
|
||||
this gives the number of lines described in the following. IN the
|
||||
example file give above this number is 2.
|
||||
#. The next line(s) contain four numbers each: index of the atom, index
|
||||
of the equivalent shell, :math:`l` quantum number, dimension
|
||||
of this shell. Repeat this line for each atomic shell, the number
|
||||
of the shells is given in the previous line.
|
||||
|
||||
In the example input file given above, we have two inequivalent
|
||||
atomic shells, one on atom number 1 with a full d-shell (dimension 5),
|
||||
and one on atom number 2 with one p-shell (dimension 3).
|
||||
|
||||
Other examples for these lines are:
|
||||
|
||||
#. Full d-shell in a material with only one correlated atom in the
|
||||
unit cell (e.g. SrVO3). One line is sufficient and the numbers
|
||||
are `1 1 2 5`.
|
||||
#. Full d-shell in a material with two equivalent atoms in the unit
|
||||
cell (e.g. FeSe): You need two lines, one for each equivalent
|
||||
atom. First line is `1 1 2 5`, and the second line is
|
||||
`2 1 2 5`. The only difference is the first number, which tells on
|
||||
which atom the shell is located. The second number is the
|
||||
same in both lines, meaning that both atoms are equivalent.
|
||||
#. t2g orbitals on two non-equivalent atoms in the unit cell: Two
|
||||
lines again. First line is `1 1 2 3`, second line `2 2 2 3`. The
|
||||
difference to the case above is that now also the second number
|
||||
differs. Therefore, the two shells are treated independently in
|
||||
the calculation.
|
||||
#. d-p Hamiltonian in a system with two equivalent atoms each in
|
||||
the unit cell (e.g. FeSe has two Fe and two Se in the unit
|
||||
cell). You need for lines. First line `1 1 2 5`, second
|
||||
line
|
||||
`2 1 2 5`. These two lines specify Fe as in the case above. For the p
|
||||
orbitals you need line three as `3 2 1 3` and line four
|
||||
as `4 2 1 3`. We have 4 atoms, since the first number runs from 1 to 4,
|
||||
but only two inequivalent atoms, since the second number runs
|
||||
only form 1 to 2.
|
||||
|
||||
Note that the total dimension of the hamiltonian matrices that are
|
||||
read in is the sum of all shell dimensions that you specified. For
|
||||
example number 4 given above we have a dimension of 5+5+3+3=16. It is important
|
||||
that the order of the shells that you give here must be the same as
|
||||
the order of the orbitals in the hamiltonian matrix. In the last
|
||||
example case above the code assumes that matrix index 1 to 5
|
||||
belongs to the first d shell, 6 to 10 to the second, 11 to 13 to
|
||||
the first p shell, and 14 to 16 the second p shell.
|
||||
|
||||
#. Number of correlated shells in the hamiltonian matrix, in the same
|
||||
spirit as line 3.
|
||||
|
||||
#. The next line(s) contain six numbers: index of the atom, index
|
||||
of the equivalent shell, :math:`l` quantum number, dimension
|
||||
of the correlated shells, a spin-orbit parameter, and another
|
||||
parameter defining interactions. Note that the latter two
|
||||
parameters are not used at the moment in the code, and only kept
|
||||
for compatibility reasons. In our example file we use only the
|
||||
d-shell as correlated, that is why we have only one line here.
|
||||
|
||||
#. The last line contains several numbers: the number of irreducible
|
||||
representations, and then the dimensions of the irreps. One
|
||||
possibility is as the example above, another one would be 2
|
||||
2 3. This would mean, 2 irreps (eg and t2g), of dimension 2 and 3,
|
||||
resp.
|
||||
|
||||
After these header lines, the file has to contain the Hamiltonian
|
||||
matrix in orbital space. The standard convention is that you give for
|
||||
each :math:`\mathbf{k}`-point first the matrix of the real part, then the
|
||||
matrix of the imaginary part, and then move on to the next :math:`\mathbf{k}`-point.
|
||||
|
||||
The converter itself is used as::
|
||||
|
||||
from triqs_dft_tools.converters.hk_converter import *
|
||||
Converter = HkConverter(filename = hkinputfile)
|
||||
Converter.convert_dft_input()
|
||||
|
||||
where :file:`hkinputfile` is the name of the input file described
|
||||
above. This produces the hdf file that you need for a DMFT calculation.
|
||||
|
||||
For more options of this converter, have a look at the
|
||||
:ref:`refconverters` section of the reference manual.
|
||||
|
||||
|
||||
Wannier90 Converter
|
||||
-------------------
|
||||
|
||||
Using this converter it is possible to convert the output of
|
||||
`wannier90 <http://wannier.org>`_
|
||||
Maximally Localized Wannier Functions (MLWF) and create a HDF5 archive
|
||||
suitable for one-shot DMFT calculations with the
|
||||
:class:`SumkDFT <dft.sumk_dft.SumkDFT>` class.
|
||||
|
||||
The user must supply two files in order to run the Wannier90 Converter:
|
||||
|
||||
#. The file :file:`seedname_hr.dat`, which contains the DFT Hamiltonian
|
||||
in the MLWF basis calculated through :program:`wannier90` with ``hr_plot = true``
|
||||
(please refer to the :program:`wannier90` documentation).
|
||||
#. A file named :file:`seedname.inp`, which contains the required
|
||||
information about the :math:`\mathbf{k}`-point mesh, the electron density,
|
||||
the correlated shell structure, ... (see below).
|
||||
|
||||
Here and in the following, the keyword ``seedname`` should always be intended
|
||||
as a placeholder for the actual prefix chosen by the user when creating the
|
||||
input for :program:`wannier90`.
|
||||
Once these two files are available, one can use the converter as follows::
|
||||
|
||||
from triqs_dft_tools.converters import Wannier90Converter
|
||||
Converter = Wannier90Converter(seedname='seedname')
|
||||
Converter.convert_dft_input()
|
||||
|
||||
The converter input :file:`seedname.inp` is a simple text file with
|
||||
the following format (do not use the text/comments in your input file):
|
||||
|
||||
.. literalinclude:: images_scripts/LaVO3_w90.inp
|
||||
|
||||
The example shows the input for the perovskite crystal of LaVO\ :sub:`3`
|
||||
in the room-temperature `Pnma` symmetry. The unit cell contains four
|
||||
symmetry-equivalent correlated sites (the V atoms) and the total number
|
||||
of electrons per unit cell is 8 (see second line).
|
||||
The first line specifies how to generate the :math:`\mathbf{k}`-point
|
||||
mesh that will be used to obtain :math:`H(\mathbf{k})`
|
||||
by Fourier transforming :math:`H(\mathbf{R})`.
|
||||
Currently implemented options are:
|
||||
|
||||
* :math:`\Gamma`-centered uniform grid with dimensions
|
||||
:math:`n_{k_x} \times n_{k_y} \times n_{k_z}`;
|
||||
specify ``0`` followed by the three grid dimensions,
|
||||
like in the example above
|
||||
* :math:`\Gamma`-centered uniform grid with dimensions
|
||||
automatically determined by the converter (from the number of
|
||||
:math:`\mathbf{R}` vectors found in :file:`seedname_hr.dat`);
|
||||
just specify ``-1``
|
||||
|
||||
Inside :file:`seedname.inp`, it is crucial to correctly specify the
|
||||
correlated shell structure, which depends on the contents of the
|
||||
:program:`wannier90` output :file:`seedname_hr.dat` and on the order
|
||||
of the MLWFs contained in it. In this example we have four lines for the
|
||||
four V atoms. The MLWFs were constructed for the t\ :sub:`2g` subspace, and thus
|
||||
we set ``l`` to 2 and ``dim`` to 3 for all V atoms. Further the spin-orbit coupling (``SO``)
|
||||
is set to 0 and ``irep`` to 0.
|
||||
As in this example all 4 V atoms are equivalent we set ``sort`` to 0. We note
|
||||
that, e.g., for a magnetic DMFT calculation the correlated atoms can be made
|
||||
inequivalent at this point by using different values for ``sort``.
|
||||
|
||||
The number of MLWFs must be equal to, or greater than the total number
|
||||
of correlated orbitals (i.e., the sum of all ``dim`` in :file:`seedname.inp`).
|
||||
If the converter finds fewer MLWFs inside :file:`seedname_hr.dat`, then it
|
||||
stops with an error; if it finds more MLWFs, then it assumes that the
|
||||
additional MLWFs correspond to uncorrelated orbitals (e.g., the O-\ `2p` shells).
|
||||
When reading the hoppings :math:`\langle w_i | H(\mathbf{R}) | w_j \rangle`
|
||||
(where :math:`w_i` is the :math:`i`-th MLWF), the converter also assumes that
|
||||
the first indices correspond to the correlated shells (in our example,
|
||||
the V-t\ :sub:`2g` shells). Therefore, the MLWFs corresponding to the
|
||||
uncorrelated shells (if present) must be listed **after** those of the
|
||||
correlated shells.
|
||||
With the :program:`wannier90` code, this can be achieved by listing the
|
||||
projections for the uncorrelated shells after those for the correlated shells.
|
||||
In our `Pnma`-LaVO\ :sub:`3` example, for instance, we could use::
|
||||
|
||||
Begin Projections
|
||||
V:l=2,mr=2,3,5:z=0,0,1:x=-1,1,0
|
||||
O:l=1:mr=1,2,3:z=0,0,1:x=-1,1,0
|
||||
End Projections
|
||||
|
||||
where the ``x=-1,1,0`` option indicates that the V--O bonds in the octahedra are
|
||||
rotated by (approximatively) 45 degrees with respect to the axes of the `Pbnm` cell.
|
||||
|
||||
The converter will analyse the matrix elements of the local Hamiltonian
|
||||
to find the symmetry matrices `rot_mat` needed for the global-to-local
|
||||
transformation of the basis set for correlated orbitals
|
||||
(see section :ref:`hdfstructure`).
|
||||
The matrices are obtained by finding the unitary transformations that diagonalize
|
||||
:math:`\langle w_i | H_I(\mathbf{R}=0,0,0) | w_j \rangle`, where :math:`I` runs
|
||||
over the correlated shells and `i,j` belong to the same shell (more details elsewhere...).
|
||||
If two correlated shells are defined as equivalent in :file:`seedname.inp`,
|
||||
then the corresponding eigenvalues have to match within a threshold of 10\ :sup:`-5`,
|
||||
otherwise the converter will produce an error/warning.
|
||||
If this happens, please carefully check your data in :file:`seedname_hr.dat`.
|
||||
This method might fail in non-trivial cases (i.e., more than one correlated
|
||||
shell is present) when there are some degenerate eigenvalues:
|
||||
so far tests have not shown any issue, but one must be careful in those cases
|
||||
(the converter will print a warning message).
|
||||
|
||||
The current implementation of the Wannier90 Converter has some limitations:
|
||||
|
||||
* Since :program:`wannier90` does not make use of symmetries (symmetry-reduction
|
||||
of the :math:`\mathbf{k}`-point grid is not possible), the converter always
|
||||
sets ``symm_op=0`` (see the :ref:`hdfstructure` section).
|
||||
* No charge self-consistency possible at the moment.
|
||||
* Calculations with spin-orbit (``SO=1``) are not supported.
|
||||
* The spin-polarized case (``SP=1``) is not yet tested.
|
||||
* The post-processing routines in the module
|
||||
:class:`SumkDFTTools <dft.sumk_dft_tools.SumkDFTTools>`
|
||||
were not tested with this converter.
|
||||
* ``proj_mat_all`` are not used, so there are no projectors onto the
|
||||
uncorrelated orbitals for now.
|
||||
|
||||
package. At the moment, there are two full charge self consistent interfaces, for the
|
||||
Wien2k and the VASP DFT packages, resp. In addition, there is an interface to Wannier90, as well
|
||||
as a light-weight general-purpose interface. In the following, we will describe the usage of these
|
||||
conversion tools.
|
||||
|
||||
.. toctree::
|
||||
:maxdepth: 2
|
||||
|
||||
conv_vasp
|
||||
conv_W90
|
||||
conv_generalhk
|
||||
|
||||
MPI issues
|
||||
----------
|
||||
==========
|
||||
|
||||
The interface packages are written such that all the file operations
|
||||
are done only on the master node. In general, the philosophy of the
|
||||
@ -542,11 +29,16 @@ yourself, you have to *manually* broadcast it to the nodes. An
|
||||
exception to this rule is when you use routines from :class:`SumkDFT <dft.sumk_dft.SumkDFT>`
|
||||
or :class:`SumkDFTTools <dft.sumk_dft_tools.SumkDFTTools>`, where the broadcasting is done for you.
|
||||
|
||||
|
||||
Interfaces to other packages
|
||||
----------------------------
|
||||
============================
|
||||
|
||||
Because of the modular structure, it is straight forward to extend the :ref:`TRIQS <triqslibs:welcome>` package
|
||||
in order to work with other band-structure codes. The only necessary requirement is that
|
||||
the interface module produces an hdf5 archive, that stores all the data in the specified
|
||||
form. For the details of what data is stored in detail, see the
|
||||
:ref:`hdfstructure` part of the reference manual.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user