  We develop a Gromacs implementation of Dimer Metadynamics[JCTC 13, 425
(2017)] for enhanced sampling through artificial delocalization effects. This
implementation is based entirely on a Plumed collective variable developed for
this purpose, the fine tuning of Gromacs input parameters, modified forcefields
and custom non-bonded interactions. We demonstrate this implementation on
Alanine Dipeptide in vacuum and in water, and on the 12-residue Alanine
Polypeptide in water and compare the results with a standard multiple-replica
technique such as Parallel Tempering. In all the considered cases this
comparison is consistent and the results with Dimer Metadynamics are smoother
and require shorter simulations, thus proving the consistency and effectiveness
of this Gromacs implementation.
