GROMACS 2021.7 release notes
----------------------------

This version was released on January 31st, 2023. These release notes
document the changes that have taken place in GROMACS since the
previous 2021.6 version, to fix known issues. It also incorporates all
fixes made in version 2020.7 and earlier, which you can find described
in the :ref:`release-notes`.

.. Note to developers!
   Please use """"""" to underline the individual entries for fixed issues in the subfolders,
   otherwise the formatting on the webpage is messed up.
   Also, please use the syntax :issue:`number` to reference issues on GitLab, without
   a space between the colon and number!

Fixes where mdrun could behave incorrectly
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Add missing net charge term when running PME on a GPU
"""""""""""""""""""""""""""""""""""""""""""""""""""""

When PME was running on a GPU, the term due to a net charge of the system was missing.
In normal runs this only changed the potential energy by a constant, which is usually
not relevant. In free-energy calculations where the net charge of the systen changes,
the would lead to incorrect dV/dlambda and Delta lambda values (but one should anyhow
avoid changing the net charge of a system with free-energy calculations).

:issue:`4668`


Fixes for ``gmx`` tools
^^^^^^^^^^^^^^^^^^^^^^^

Fixes that affect portability
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Miscellaneous
^^^^^^^^^^^^^