We use seven solute-solvent systems to investigate the errors introduced by the QM/MM-PHVA approach on normal modes, frequencies, IR intensities, and Raman intensities. The systems consist of single solute molecules surrounded by multiple solvent molecules: furan in benzene, naphthalene in acetonitrile, pyridine in methanol, 1,3-butadiene in water, uracil in methanol, propanamide in water, and formaldehyde in water. The starting structures were obtained from Reinholdt et al. First, we extracted spheres with an 8 Å radius, where the center of mass of the solutes is at the center of the spheres. Preliminary calculations indicated that using an 8 Å radius yields similar frequencies and intensities compared to larger radii, up to 24 Å. Furthermore, the exact system size is not critically important since these structures are used for internal comparison. We also prepared small model systems of pyridine in methanol, 1,3-butadiene in water, uracil in methanol, propanamide in water, and formaldehyde in water by removing most solvent molecules. Thus, between 4 and 11 solvent molecules surrounding the solute molecules were kept (more details in Table ).