Summary
Hydrogen mass repartitioning is a technique used to speed up MD simulations where the mass of hydrogen atoms is increased from 1 amu to 3 amu, and the mass of covalently bound heavy atoms is accordingly reduced. It allows a 4 femtosecond time step as opposed to a 2 fs time step, halving simulation times. However, it has been shown to lead to reduced Brownian motion and slower dynamics.