The resulting spectra, simulated with both Q/s and C/d, alongside the experimental one , are shown in Figure . Focusing first on the experimental data, it is evident that for all concentrations, there are a number of bands that remain nearly unchanged. These can be associated with the monomer, at approximately 3600 cm -1 , and CH stretching vibrations (the double-peaked band around 3000 cm -1 ). Both of these features are identifiable in the simulated spectra with Q/s and C/d methods, with slight deviations in position that can be attributed to the usual inaccuracies in DFT-computed frequencies at the harmonic level.