symWannier 1.1.0

A python package for computing symmetry adapted Wannier functions with irreducible BZ

symWannier

A collection of codes to construct Wannier functions using crystal symmetry. By using this package, users only need to calculate the wave functions, overlap matrices (Mmn), and projection matrices (Amn) in the irreducible Brillouin zone (IBZ). Mmn and Amn files for the full Brillouin zone, required by the wannier90 package, can be generated using the symmetry information. Users can also use the Python scripts included in this package to construct maximally-localized Wannier functions. There is an option to calculate symmetry-adapted Wannier functions.

Installation

First, please download the scripts:

git clone [e-mail]:wannier-utils-dev/symWannier.git

Then, install the package using pyproject.toml. This can be done with pip inside the cloned directory:

pip install .

IBZ calculation using wannier90

Run SCF and NSCF calculations to obtain wave functions in the irreducible Brillouin zone (IBZ).

pw.x < scf.in
pw.x < nscf.in

In the NSCF calculation, k-points should be generated automatically as

K_POINTS {automatic}
8 8 8 0 0 0

Prepare prefix.win and generate prefix.nnkp. You can use the same prefix.win that is used in the original wannier90 calculation.

wannier90.x -pp prefix

Run pw2wannier90.x with irr_bz = .true. to compute prefix.immn, prefix.iamn, prefix.ieig. Symmetry infomation is stored in prefix.isym.

Note: Quantum ESPRESSO version 7.3 or later is required for this step.

pw2wannier90.x < pw2wan.in

Calculate Mmn, Amn and Eig in the full BZ using expand_wannier_inputs.py.

symwannier expand prefix

Run wannier90 as usual.

wannier90.x prefix

There are sample input and script files, in examples/Cu and examples/Fe.

Symmetry adapted Wannier functions

Once prefix.immn, prefix.iamn, prefix.ieig, and prefix.isym are obtained, you can construct Wannier functions as follows.

symwannier wannierize -s prefix

To construct symmetry-adapted Wannier functions, use the "-S" option instead of "-s".

symwannier wannierize -S prefix

Paper

For more information, please see T. Koretsune, Comp. Phys. Comm. 285 108645 (2023).

We hope that you cite this reference when you publish the results using this code.