axtb: licenses
==============

axtb (https://github.com/atomsforhumanity/axtb) is free software under two licenses. The full
texts are in the repository's top directory:
COPYING (GNU General Public License, version 3) and COPYING.LESSER (GNU Lesser General Public
License, version 3, which supplements the GPL and needs it alongside).

LGPL-3.0-or-later (COPYING.LESSER with COPYING)
  crates/axtb        axtb            GFN2-xTB and the shared machinery
  crates/d4          axtb-d4         DFT-D4 dispersion
  crates/solvation   axtb-solvation  ALPB/GBSA implicit solvation
  crates/gfnff       axtb-gfnff      GFN-FF force field

  These crates reproduce parameters and algorithms of xtb, tblite and dftd4 (LGPL-3.0-or-later)
  and data of mctc-lib and multicharge (Apache-2.0); see NOTICE.

GPL-3.0-only (COPYING)
  crates/gxtb        axtb-gxtb       g-xTB v1.1 and 2.0.1
  crates/driver      axtb-driver     the request/response layer of the front ends
  crates/axtb-cli    axtb-cli        the `axtb` command-line program
  crates/axtb-py     axtb (PyPI)     the Python package and its wheels

  axtb-gxtb is GPL-3.0-only because it embeds the g-xTB parameters: the parameter files of
  the g-xTB 1.1.0 release and tables taken from the g-xTB 1.1.0 and 2.0.1 programs
  (grimme-lab/g-xtb, GPL-3.0). axtb-driver, axtb-cli and axtb-py build axtb-gxtb in by
  default (Cargo feature `gxtb`), so they, the `axtb` program and the Python wheels are
  GPL-3.0-only as built by default.

Builds without g-xTB
  The code of axtb-driver, axtb-cli and axtb-py contains no g-xTB parameters; they reach
  axtb-gxtb only through the feature `gxtb`. Built with `--no-default-features`
  (`cargo build -p axtb-cli --no-default-features`,
  `maturin build --no-default-features -m crates/axtb-py/Cargo.toml`), they contain nothing
  from axtb-gxtb, and the result is LGPL-3.0-or-later: GFN2-xTB and GFN-FF, without g-xTB.

Other files
  third_party/   patched copies of two MIT-licensed crates (gemm-common, private-gemm-x86);
                 each keeps its own LICENSE file (third_party/README.md).
  tests/structures/README.md  the source and license of each test structure.

Each published crate carries the license texts it needs (COPYING, and COPYING.LESSER for the
LGPL crates and for the crates whose build without g-xTB is LGPL) and NOTICE.
