# Documentation of the inputs of the aiida-wannier90 plugin¶

## Inputs¶

### parameters¶

A Dict node containing the input parameters for the Wannier90 calculation to be performed. Unlike the Wannier90 code, which does not check capitilization (see the Wannier90 documentation for more details), this plugin is case sensitive. All keys must be lowercase, e.g. num_wann is acceptable but NUM_WANN is not.

### structure¶

A StructureData node with the crystal structure.

### kpoints¶

A KpointsData node containing the reciprocal space k-points used to build the Wannier functions. This must be an evenly-spaced grid and must be constructed using an mp_grid k-point mesh that should be the same used in the NSCF step of the preliminary DFT calculation.

If you are using aiida-quantumespresso for the preliminary DFT calculations, you can construct the explicit list of k-points using {'FORCE_KPOINTS_LIST': True} in the settings of the calculation. In this case, for Quantum ESPRESSO set also nosym=True in the SYSTEM namelist of the NSCF step.

### remote_input_folder¶

A RemoteData node pointing to a folder with the needed preliminary files, stored on a remote computer. These include both the files created by a DFT post-processing code (.amn, .mmn, …) and/or the .chk checkpoint file created by Wannier90 and needed in a restart. This folder must not be specified when running Wannier90 in post-processing mode (-pp option). See also the option postproc_setup in the input settings node.

See Files Copied for more details.

### local_input_folder¶

A FolderData node containing the needed preliminary files (as for the remote_input_folder).

This folder must not be specified when running Wannier90 in post-processing mode (-pp option). See also the option postproc_setup in the input settings node.

The two inputs remote_input_folder and local_input_folder cannot be specified at the same time. You can choose between them depending on whether you decided to store the preliminary files (.amn, .mmn, …) in the AiiDA repository, or just on the supercomputer.

See Files Copied for more details.

### kpoints_path¶

An optional Dict node, specifying a set of pairs of k-points. These define the endpoints of each segment along which to plot a band structure. I must contain, in particular:

• a list path of length-2 tuples with the labels of the endpoints of the path;

• a dictionary point_coords giving the scaled coordinates for each high-symmetry endpoint.

### projections¶

A specification of which projections to use for the Wannierisation. Multiple node types are accepted as discussed below.

You can construct the projections using the convenience method generate_projections().

This will produce an OrbitalData node startinf from a list of dictionaries specifying the projection-orbital symmetries and properties.

Some examples, taken directly from the wannier90 user guide:

• Material: CuO. $$s$$, $$p$$, and $$d$$ orbitals on all Cu atoms, and $$sp^3$$ hyrbrids on all oxygen atoms.

In Wannier90 one would specify:

Cu:l=0;l=1;l=2
O:l=-3


(or O:sp3).

The list of dictionaries to provide to generate_projections() is:

[
{
'kind_name': 'Cu',
'ang_mtm_name': ['SP','P','D']
},
{
'kind_name': 'O',
'ang_mtm_l_list':-3
}
]


(or equivalently {..., 'ang_mtm_name': ['SP3']}).

• A single projection onto a $$p_z$$ orbital orientated in the (1, 1, 1) direction.

In Wannier90:

c=0,0,0:l=1:z=1,1,1


or c=0,0,0:pz:z=1,1,1.

The list of dictionaries to provide to generate_projections() is:

[
{
'position_cart': (0,0,0)
'ang_mtm_l_list': 1,
'zaxis':(1,1,1)
}
]


or {... , 'ang_mtm_name':'PZ',...}.

• Project onto $$s$$, $$p$$, and $$d$$ orbitals (with no radial nodes), and $$s$$ and $$p$$ (with one radial node) in silicon.

In Wannier90:

Si:l=0;l=1;l=2
Si:l=0;l=1;r=2


The list of dictionaries to provide to generate_projections() is:

[
{
'kind_name': 'Si',
'ang_mtm_l_list': [0,1,2]
},
{
'kind_name': 'Si',
'ang_mtm_l_list': [0,1],
}
]


### settings¶

A Dict node with additional settings to control the Wannier90 calculation. It can contain the following file handling options:

• additional_retrieve_list: List of additional filenames to be retrieved.

• additional_remote_symlink_list: List of custom files to link on the remote.

• additional_remote_copy_list: List of custom files to copy from a different folder on the remote.

• additional_local_copy_list: List of custom files to copy from a local source (a folder in the AiiDA repository).

• exclude_retrieve_list: List of filename patterns to exclude when retrieving. It does not affect files listed in additional_retrieve_list.

Besides, the following general options are available:

• random_projections: Enables using random projections if not enough projections are defined.

• postproc_setup: Use Wannier90 in preprocessing mode. This affects which input and output files are expected (see .

## Files Copied¶

Which files are copied and which are symlinked during the upload phase (or a calculation having a remote_input_folder or a folder_input_folder depends on the startup settings used, and what the parent calculation was.

The goal is to copy the minimum number of files. However, we do not symlink files that are rewritten during the run (e.g. the .chk file), as in this case multiple runs (restarts) could try to change the same file.

The list of files to copy or symlink is generated from the content of the local_input_folder or remote_input_folder, which are mutually exclusive. The following operations will be performed on the files:

• copy: the file, if present, is copied from the parent;

• nothing: the file will neither be copied nor symlinked.

In particular, the files .amn and .mmn are always required and are symlinked. Additional input files (that are not required, as they are needed only for some types of calculations) are symlinked, if present: .eig, .spn, .uHu, _htB.dat, _htL.dat, _htR.dat, _htC.dat, _htLC.dat, _htCR.dat, .unkg.

To add some files in the list to copy or symlink on the remote, or to copy from the AiiDA repository, the user can modify the corresponding file list in the settings node: additional_remote_symlink_list, additional_remote_copy_list and additional_local_copy_list.

At variance, the file .chk is not required ,but if present is always copied by default (since this can be overwritten).

### Retrieved files¶

All the output files of Wannier90 are retrieved by default, if present, except the .nnkp file (which is handled separately and stored as a SinglefileData node for a postproc_setup calculation) and the .chk file (checkpoint files are large and usually not needed, so by default they are not retrieved.

Here is the complete list of suffixes of the files to retrieve: .wout, .werr, .r2mn, _band.dat, _band.agr, _band.kpt, .bxsf, _w.xsf, _w.cube, _centres.xyz, _hr.dat, _tb.dat, _r.dat, .bvec, _wsvec.dat, _qc.dat, _dos.dat, _htB.dat, _u.mat, _u_dis.mat, .vdw, _band_proj.dat, _band.labelinfo.dat.

To exclude or include specific files from the retrieved list, one can respectively use the exclude_retrieve_list and additional_retrieve_list settings described above.