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Added docs on PLOVasp
Added description of the input file and a general section on the interface. Also, an example input file for SrVO3 is added.
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Oleg E. Peil
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@ -181,6 +181,70 @@ since we need also the :program:`optics` package of Wien2k. Please
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look at the section on :ref:`Transport` to see how to do the necessary
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steps, including the conversion.
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Interface with VASP
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---------------------
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The interface with VASP relies on new options introduced since
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version 5.4.x. The output of raw (non-normalized) projectors is
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controlled by an INCAR option LOCPROJ whose complete syntax is described in
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VASP documentaion.
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The definition of a projector set starts with specifying which sites
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and which local states we are going to projecto onto.
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This information is provided using option LOCPROJ
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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 (e.g. :math:`s`, :math:`p`, :math:`d`,
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:math:`d_{x^2-y^2}`, etc.);
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`<projector type>` chooses a particular type of the local basis function.
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Some projector types also require parameters `EMIN`, `EMAX` in INCAR to
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be set to define an (approximate) energy window corresponding to the
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valence states.
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When either a self-consistent (`ICHARG < 10`) or a non-self-consistent
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(`ICHARG >= 10`) calculation is done VASP produces file `LOCPROJ` which
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will serve as the main input for the conversion routine.
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Conversion for the DMFT self-consistency cycle
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""""""""""""""""""""""""""""""""""""""""""""""
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In order to use the projectors generated by VASP for defining an
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impurity problem they must be processed, i.e. normalized, possibly
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transformed, and then converted to a format suitable for DFT_tools scripts.
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The processing of projectors is performed by the program :program:`plovasp`
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invoked as
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| `plovasp <plo.cfg>`
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where `<plo.cfg>` is a input file controlling the conversion of projectors.
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The format of input file `<plo.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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A general H(k)
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--------------
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8
doc/guide/images_scripts/srvo3.cfg
Normal file
8
doc/guide/images_scripts/srvo3.cfg
Normal file
@ -0,0 +1,8 @@
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[Shell 1]
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LSHELL = 2
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IONS = 2
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EWINDOW = -1.45 1.8
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TRANSFORM = 1.0 0.0 0.0 0.0 0.0
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0.0 1.0 0.0 0.0 0.0
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0.0 0.0 0.0 1.0 0.0
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@ -25,7 +25,7 @@ raw projectors. Note, however, that DFTtools does not support projector
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groups at the moment but this feature might appear in future releases.
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A set of projectors defined on sites realted to each other either by symmetry
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or by sort along with a set of `l`, `m` quantum numbers forms a
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or by sort along with a set of :math:`l`, :math:`m` quantum numbers forms a
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`projector shell`. There could be several projectors shells in a
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projector group, implying that they will be normalized within
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the same energy window.
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@ -45,13 +45,97 @@ A PLOVasp input file can contain three types of sections:
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#. **[General]**: includes parameters that are independent
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of a particular projector set, such as the Fermi level, additional
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output (e.g. the density of states), etc.
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#. **[Group <Ng>]**: describes projector groups, i.e. a set of
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projectors sharing the same energy window and normalization type.
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At the moment, DFTtools support only one projector group, therefore
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there should be no more than one projector group.
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#. **[Shell <Ns>]**: contains parameters of a projector shell labelled
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with `<Ns>`. If there is only one group section and one shell section,
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the group section can be omitted and its required parameters can be
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given inside the single shell section.
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Section [General]
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"""""""""""""""""
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The entire section is optional and it contains three parameters:
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* **BASENAME** (string): provides a base name for output files.
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Default filenames are :file:`vasp.*`.
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* **DOSMESH** ([float float] integer): if this parameter is given
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projected density of states for each projected orbital will be
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evaluated and stored to files :file:`pdos_<n>.dat`, where `n` is the
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orbital number. The energy
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mesh is defined by three numbers: `EMIN` `EMAX` `NPOINTS`. The first two
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can be omitted in which case they are taken to be equal to the projector
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energy window. **Important note**: at the moment this option works
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only if the tetrahedron integration method (`ISMEAR = -4` or `-5`)
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is used in VASP to produce `LOCPROJ`.
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* **EFERMI** (float): provides the Fermi level. This value overrides
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the one extracted from VASP output files.
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There are no required parameters in this section.
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Section [Shell]
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"""""""""""""""
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This section specifies a projector shell. Each shell section must be
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labeled by an index, e.g. `[Shell 1]`. These indices can then be referenced
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in a `[Group]` section.
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In each `[Shell]` section two parameters are required:
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* **IONS** (list of integer): indices of sites included in the shell.
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The sites can be given either by a list of integers `IONS = 5 6 7 8`
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or by a range `IONS = 5..8`. The site indices must be compatible with
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POSCAR file.
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* **LSHELL** (integer): :math:`l` quantum number of the desired local states.
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It is important that a given combination of site indices and local states
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given by `LSHELL` must be present in LOCPROJ file.
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There are additional optional parameters that allow one to transform
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the local states:
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* **TRANSFORM** (matrix): local transformation matrix applied to all states
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in the projector shell. The matrix is defined by (multiline) block
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of floats, with each line corresponding to a row. The number of columns
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must be equal to :math:`2 l + 1`, with :math:`l` given by `LSHELL`. Only real matrices
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are allowed. This parameter can be useful to select certain subset of
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orbitals or perform a simple global rotation.
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* **TRANSFILE** (string): name of the file containing transformation
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matrices for each site. This option allows for a full-fledged functionality
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when it comes to local state transformations. The format of this file
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is described in :ref:`_transformation_file`.
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Section [Group]
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"""""""""""""""
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Each defined projector shell must be part of a projector group. In the current
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implementation of DFTtools only a single group is supported which can be
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labeled by any integer, e.g. `[Group 1]`. This implies that all projector shells
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must be included in this group.
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Required parameters for any group are the following:
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* **SHELLS** (list of integers): indices of projector shells included in the group.
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All defined shells must be grouped.
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* **EWINDOW** (float float): the energy window specified by two floats: bottom
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and top. All projectors in the current group are going to be normalized within
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this window.
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Optional group parameters:
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* **NORMALIZE** (True/False): specifies whether projectors in the group are
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to be noramlized. The default value is **True**.
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* **NORMION** (True/False): specifies whether projectors are normalized on
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a per-site (per-ion) basis. That is, if `NORMION = True` the orthogonality
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condition will be enforced on each site separately but the Wannier functions
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on different sites will not be orthogonal. If `NORMION = False` Wannier functions
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on different sites included in the group will be orthogonal to each other.
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.. _transformation_file
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File of transformation matrices
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"""""""""""""""""""""""""""""""
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