SOLVENT EFFECTS ON THE INFRARED FREQUENCY OF THE N-C BAND IN ISON1TRILES AND THE SIGN OF $\partial \mu/\partial $r

Author Institution: JR., Department of Chemistry, Princeton UniversitySpectra in the N-C stretching region are recorded for t-butyl and p-tolyl isonitriles in the vapor phase and in solution in 14 solvents. A number of solvents were found to shift the N -C band to frequencies higher than the vapor phase value. The N-C band shifts in solution correlate qualitatively with the theory of Drickamer and co-workers and allow us to assign a negative sign to $\partial_{\mu}/\partial_{r}$ for the N-C stretching vibration. A band at frequencies considerably higher than the vapor phase value is found for solutions of isonitriles in hydrogen -bonding solvents