Numerous studies have been made on the effect of solvents on the ir frequency shifts of various functional groups (see reviews by Rao and Hallam). Solvents of varying polarities are used and it has been found that there is some correlation between the dielectric constant of the solvent and the frequency shift. These studies are often limited by the strong ir absorption of the solvents in various regions.
Neal L. McNiven and Richard Court, "Infrared Spectra of Deuterated Solvents," Appl. Spectrosc. 24, 296-300 (1970)