The calculated IR spectra are in general consistent with experimental IR spectra, whereas conventional DFT often struggles with both frequencies and intensities for the PTMs. We also evaluated the performance of two widely used multicomponent electron-proton correlation functionals (epc17-1 and epc17-2) within the CNEO framework. The calculated vibrational frequencies are sensitive to the choice of the functionals. Notably, the epc17-1 functional yields inaccurate vibrational frequencies similar to those from DFT calculations, suggesting its use should be avoided for calculating molecular vibrational frequencies in CNEO. In contrast, incorporating the epc17-2 functional in CNEO calculations provides frequencies comparable to those obtained at the no-epc level. Given the additional computational burden of including electron-proton correlation functionals, we recommend performing CNEO calculations at the no-epc level for molecular vibrations.