This discrepancy likely arises from conformational flexibility associated with a relatively flat potential surface and the sensitivity of OH stretching frequencies to hydrogen bonding in this region. Accurately capturing this effect would require incorporating contributions from out-of-equilibrium structures, which, while accessible through the C/d protocol, lies beyond the scope of this study. Instead, we address this phenomenon phenomenologically by applying larger Gaussian broadening specifically in this region to account for inhomogeneous broadening. This adjustment results in smoother curves that more closely resemble the experimental band. Specifically, we apply Gaussian broadening with a half-width at half maximum (HWHM) of 60 cm -1 in the 3150-3600 cm -1 region while retaining a Lorentzian broadening with HWHM of 10 cm -1 in the rest of the spectral region.