supercell-step 2025.6.25.1
A SEAMM plug-in for building supercells of periodic systems.
License: BSD-3-Clause
Keywords: SEAMM, plug-in, flowchart, supercell, unitcell, periodic, atomistic

==============
Supercell Step
==============

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A SEAMM plug-in for building supercells of periodic systems.

* Free software: BSD-3-Clause
* Documentation: https://molssi-seamm.github.io/supercell_step/index.html
* Code: https://github.com/molssi-seamm/supercell_step

Features
--------

* Currently only accepts na, nb, and nc, the numbers of cells in the
  three directions.
* To do:

  - Create a supercell with a minimum dimension, e.g. 10 Å.
  - Create orthorhombic cells from hexagonal ones.
  - Build using the primitive cell rather than conventional.

Acknowledgements
----------------

This package was created with Cookiecutter_ and the `molssi-seamm/cookiecutter-seamm-plugin`_ project template.

.. _Cookiecutter: https://github.com/audreyr/cookiecutter
.. _`molssi-seamm/cookiecutter-seamm-plugin`: https://github.com/molssi-seamm/cookiecutter-seamm-plugin

Developed by the Molecular Sciences Software Institute (MolSSI_),
which receives funding from the `National Science Foundation`_ under
award OAC-1547580 and CHE-2136142.

.. _MolSSI: https://www.molssi.org
.. _`National Science Foundation`: https://www.nsf.gov


=======
History
=======
2025.6.25.1 -- Bugfix: fixed crash caused by gradients.
    * The addition of the gradients to the atom data caused a crash when expanding the
      cell. Since it doesn't obviously make sense to expand the gradients, they are
      ignored when building a supercell.

2025.6.25 -- Bugfix: avoid lowering symmetry for P1 systems.

2023.11.5 -- Updated to handle symmetry in systems

2021.2.12 --
    * Updated the README file to give a better description.
    * Updated the short description in setup.py to work with the new installer.
    * Added keywords for better searchability.

2021.2.4 --
    * Updated for compatibility with the new system classes in MolSystem
      2021.2.2 release.

2020.12.5 -- 
    * Added support for non-orthorhombic cells.
    * Updated to be compatible with the new system classes in MolSystem.
    * Internal: switching CI from TravisCI to GitHub Actions, and in the
      process moving documentation from ReadTheDocs to GitHub Pages where
      it is consolidated with the main SEAMM documentation.

0.9.1 -- 20 June 2020
    * Bugfix: Was not properly copying charges to the new system.

0.9 -- 18 June 2020
    * First release on PyPI.
    * Working but only for orthorhombic cells