/usr/lib/x86_64-linux-gnu/libgromacs_d.so is in libgromacs-dev 5.1.2-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libgromacs_d.so.1
/usr/lib/x86_64-linux-gnu/libgromacs_d.so.1