DFTB+: general package for performing fast atomistic calculations

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DFTB+ is a software package for carrying out fast quantum mechanical atomistic calculations based on the Density Functional Tight Binding method. The most recent features are described in the (open access) DFTB+ paper <https://doi.org/10.1063/1.5143190>_.

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DFTB+ can be either used as a standalone program or integrated into other software packages as a library.

Installation

Obtaining via Conda

The preferred way of obtaining DFTB+ is to install it via the conda package management framework using Miniconda <https://docs.conda.io/en/latest/miniconda.html>_ or Anaconda <https://www.anaconda.com/products/individual>_. Make sure to add/enable the conda-forge channel in order to be able to access DFTB+. (Please consult the conda documentation for how to set-up your conda environment.)

We recommend the use of the mamba installer <https://mamba.readthedocs.io/>_, as we have experienced dependency resolution problems with the original conda installer in the past::

conda install -n base mamba

We provide several build variants, choose the one suiting your needs. For example, by issuing ::

mamba install 'dftbplus==nompi_'

or ::

mamba install 'dftbplus==mpi_mpich_'

or ::

mamba install 'dftbplus==mpi_openmpi_'

to get the last stable release of DFTB+ with, respectively, serial (OpenMP-threaded) build or with MPI-parallelized build using either the MPICH or the Open MPI framework.

Downloading the binary

A non-MPI (OpenMP-threaded) distribution of the latest stable release can be found on the stable release page <http://www.dftbplus.org/download/dftb-stable/>_.

Building from source

Note: This section describes the building with default settings (offering only a subset of all possible features in DFTB+) in a typical Linux environment. For more detailed information on the build customization and the build process, consult the detailed building instructions in INSTALL.rst <INSTALL.rst>_.

Download the source code from the stable release page <http://www.dftbplus.org/download/dftb-stable/>_.

You need CMake (>= 3.16) to build DFTB+. If your environment offers no CMake or only an older one, you can easily install the latest CMake via Python's pip command::

pip install cmake

Start CMake by passing your compilers as environment variables (FC and CC), and the location where the code should be installed and the build directory (_build) and als options::

FC=gfortran CC=gcc cmake -DCMAKE_INSTALL_PREFIX=$HOME/opt/dftb+ -B _build .

If the configuration was successful, start the build with::

cmake --build _build -- -j

After successful build, you should test the code. First download the SK-files needed for the test ::

./utils/get_opt_externals slakos

and then run the tests with ::

pushd _build; ctest -j; popd

If the tests were successful, install the package with ::

cmake --install _build

For further details see the detailed building instructions <INSTALL.rst>_.

Parameterisations

In order to carry out calculations with DFTB+, you need according parameterisations (a.k.a. Slater-Koster files). You can download them from dftb.org <https://dftb.org>_.

Documentation

Consult following resources for documentation:

• Step-by-step instructions with selected examples (DFTB+ Recipes) <http://dftbplus-recipes.readthedocs.io/>_

• Reference manual describing all features (DFTB+ Manual) <http://www.dftbplus.org/fileadmin/DFTBPLUS/public/dftbplus/latest/manual.pdf>_

Citing

When publishing results obtained with DFTB+, please cite following works:

• DFTB+, a software package for efficient approximate density functional theory based atomistic simulations; J. Chem. Phys. 152, 124101 (2020) <https://doi.org/10.1063/1.5143190>_

• Reference publications of the Slater-Koster parameterization sets you used. (See dftb.org <https://dftb.org>_ for the references.)

• Methodological papers relevant to your calculations (e.g. excited states, electron-transport, third order DFTB etc.). References to these can be found in the DFTB+ manual <http://www.dftbplus.org/fileadmin/DFTBPLUS/public/dftbplus/latest/manual.pdf>_.

Contributing

New features, bug fixes, documentation, tutorial examples and code testing is welcome in the DFTB+ developer community!

The project is hosted on github <http://github.com/dftbplus/>. Please check CONTRIBUTING.rst <CONTRIBUTING.rst> and the DFTB+ developers guide <https://dftbplus-develguide.readthedocs.io/>_ for guide lines.

We are looking forward to your pull request!

License

DFTB+ is released under the GNU Lesser General Public License. See the included LICENSE <LICENSE>_ file for the detailed licensing conditions.

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