To determine the minimum number of snapshots and the optimal time step between them for obtaining converged spectra, it is necessary to benchmark the sample size. This involves examining how the convergence of frequencies and intensities calculated for the ensemble of snapshots depends on different step sizes between snapshots and varying total numbers of snapshots. After extracting a suitable number of structures, they are partitioned into a core subsystem and an environment subsystem. The environment can be further subdivided into different subsystems, e.g., into an inner polarizable part and an outer non-polarizable part, as illustrated in Figure , to reduce the computational cost. For this step, the size of the molecular environment must be benchmarked to ensure that the vibrational frequencies and intensities are converged with respect to the system size.