Simulating chemically
reactive phenomena such as proton transport
on nanosecond to microsecond and beyond time scales is a challenging
task. Ab initio methods are unable to currently access
these time scales routinely, and traditional molecular dynamics methods
feature fixed bonding arrangements that cannot account for changes
in the system’s bonding topology. The Multiscale Reactive Molecular
Dynamics (MS-RMD) method, as implemented in the Rapid Approach for
Proton Transport and Other Reactions (RAPTOR) software package for
the LAMMPS molecular dynamics code, offers a method to routinely sample
longer time scale reactive simulation data with statistical precision.
RAPTOR may also be interfaced with enhanced sampling methods to drive
simulations toward the analysis of reactive rare events, and a number
of collective variables (CVs) have been developed to facilitate this.
Key advances to this methodology, including GPU acceleration efforts
and novel CVs to model water wire formation are reviewed, along with
recent applications of the method which demonstrate its versatility
and robustness.