Molecular dynamics with enhanced sampling techniques often required expensive collective variables to be computed on the fly, resulting in a significant slowing down of the simulation. In our research we use several techniques based on collective variables and we sometime find this extra cost unacceptable. For this reason, we developed a new scheme that can be used to decrease this cost by computing collective variables every few molecular dynamics steps. Even better, we introduced a theoretical framework that can be used to assess the discretization errors and, as a matter of fact, to use this technique safely.
The method is implemented in a separate branch of the PLUMED plugin, and will be merged before next release of this software. All the details can be found in a paper just accepted on J. Chem. Theory Comput. A preprint is available at arXiv:1412.3916.