Hi, all older versions are available on gromacs website https://www.gromacs.org/Downloads_of_outdated_releases

In case you cannot download it directly from the website --

1. copy the version link

2. Go to your terminal, type 'wget version_link'

You get everything!!

1. copy the version link

2. Go to your terminal, type 'wget version_link'

Example: for gromacs/4.6.1

type 'wget ftp.gromacs.org/pub/gromacs/gromacs-4.6.1.tar.gz' in terminal

for gromacs 4.6; type 'wget ftp.gromacs.org/pub/gromacs/gromacs-4.6.tar.gz'

Thank you