Experimental measurements of the OH IR frequencies of 2-methoxy-ethanol were taken from Ref. . The same optimization process as used for the NMR comparison was applied. The vibrational frequencies in the QM calculations with SMD and QM-GNNIS were calculated based on the Hessians obtained during the free-energy calculations. The frequencies were broadened using Gaussians with a σ of 5 Hz, and the total spectrum was obtained as the population-weighted sum over all conformers. As openCOSMO-RS does not allow the calculation of Hessians, the frequencies of the SMD model were used with the population weights obtained using openCOSMO-RS.