be computed similarly. The duration (t tot ) and the time step (∆t) of ACF are the same as for the original MD trajectory. In discrete Fourier transform, the frequency resolution is determined by the trajectory duration as ∆ν ∝ t -1 tot , while the time step determines the maximal frequency as ν max ∝ ∆t -1 . Generally, it is recommended to use small time steps in MD simulations, otherwise large integration steps can lead to artificial blue shifts in the highfrequency region. However, such shifts can be corrected using a simple replacement of Fourier-transform frequencies ν FT with