Rethinking Metadynamics - https://pubs.acs.org/doi/10.1021/acs.jpclett.0c00497 - https://arxiv.org/abs/1909.07250
This repository contains all the input files and scripts needed to reproduce the results of the paper, and all the data used to produce the figures. The software used is PLUMED 2.7 and GROMACS 2018.4
OPES is available as contributed PLUMED module, see https://www.plumed.org/doc-master/user-doc/html/_o_p_e_s.html
For a more recent introduction to the OPES method see this PLUMED masterclass (git repo here).