elphmod 0.1

This is a collection of Python modules to handle electron-phonon models:

• el - tight-binding models from Wannier90
• ph - mass-spring models from Quantum ESPRESSO
• elph - electron-phonon coupling from EPW
• elel - Coulomb interaction from VASP
• MPI - work distribution and shared memory
• bravais - lattices, symmetries, and interpolation
• dispersion - diagonalization on paths and meshes
• dos - 2D tetrahedron methods
• diagrams - susceptibilities, self-energies, etc.
• occupations - step and delta smearing functions
• eliashberg - parameters for McMillan's formula
• plot - BZ plots, color models, and fatbands
• misc - status bars etc.

Installation

To install the latest version of elphmod in a virtual environment:

python3 -m venv elphmod.venv
source elphmod.venv/bin/activate
python3 -m pip install --upgrade pip setuptools wheel
python3 -m pip install elphmod

Alternatively, to install the latest development version:

python3 -m pip install git+https://github.com/janberges/elphmod

elphmod can optionally be run in parallel via MPI (with shared-memory support). Using APT and pip, you can install the corresponding dependencies as follows:

sudo apt install libopenmpi-dev
python3 -m pip install mpi4py --no-binary=mpi4py

If you plan to work on elphmod itself, we recommend to download the complete repository and install all requirements (including those of documentation and examples) and a link to the repository in your home directory:

git clone https://github.com/janberges/elphmod
python3 -m pip install --user -r elphmod/requirements.txt
python3 -m pip install --user -e elphmod

Please note that scripts are still copied rather than linked. To circumvent this, you can alternatively install elphmod by prepending the absolute paths to elphmod/elphmod and elphmod/bin to the environment variables PYTHONPATH and PATH, respectively.

Documentation

All functions are documented directly in the source files using NumPy-style docstrings. You can generate an automatic documentation in HTML format using Sphinx:

cd doc
make html
firefox html/index.html

Please also have a look at the examples:

cd examples
mpirun python3 electrons.py
mpirun python3 phonons.py

Licence

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.

Copyright (C) 2021 elphmod Developers