To benchmark the sample size, we defined windows of different step sizes and numbers of snapshots, for which we calculated the average frequencies, IR intensities, and Raman intensities. We calculated the average window error δ by first calculating the average frequencies and intensities µ i,j for each window i for each individual normal mode j. Then, we calculated the absolute error by subtracting the value of the reference window µ ref for each normal mode of each window: