Third GROMACS 2021 beta released

Hi GROMACS users,

Thanks to all of you who tested the GROMACS 2021 beta releases! Thanks to you, we improved a couple of things on the earlier betas and are proud to announce the third beta release of GROMACS 2021!

We are making this available to you to get an early taste of how GROMACS
2021 will look and work, and most importantly to get feedback from you
about how well things work. While we try our hardest to keep the quality of
GROMACS as high as possible, we’re human, we overlook things while doing
other things, and we need your many pairs of eyes to help build a tool that
we can all use to do good science! We really need you to test your kinds of
simulation on your hardware, both for correctness and performance. This is
particularly important if you are using “interesting” hardware or
compilers, because we can’t test all of them!

Please do not use this version for doing science you plan to publish - it
needs more testing before it’s reliable enough for that. Similarly, please
don’t use this version as a base for a project that bundles or forks

What new things can you expect? (See the release notes for more details.)

  • Free energy perturbation with AWH
  • Support for ARM SVE
  • Multiple time stepping simulations
  • Stochastic rescaling barostat for equilibration and production
  • PME offloading to GPUs also for free energy simulations
  • API for nonbonded interactions with NB-LIB

There are lots of other new things, and a few old things removed - please see
the release notes for the complete list. All the content of GROMACS 2020.4
is present, apart from features that have been removed. Your testing helps us develop the next beta. To follow progress have a look at the 2021-rc1 milestone on gitlab and report issues there .

If all goes to plan, we hope to ship the final 2021 release in the middle
of January next year, but that relies on people joining in and helping us test! We hope you will consider making that contribution, so that we can continue to
deliver high-quality free simulation software that will be useful to you.

Find the code, manual, release notes, installation instructions and
testsuite at the links below.

(includes install guide, user guide, reference manual)
Release Notes:
Test Suite:

Happy testing!