Infrared depletion spectroscopy of aniline–(CH 3) 2O cluster and corresponding cluster cation

Abstract

The infrared spectra of the NH stretching vibrations of aniline–(CH 3) 2O cluster and corresponding cluster cation in 3200–3600 cm −1 region have been measured using the infrared depletion method. There are two strong absorption bands at 3383 and 3485 cm −1 in the spectrum of aniline–(CH 3) 2O cluster. The vibrational analysis has shown that one of the NH bonds of aniline interacts with the lone pair of the oxygen atom of (CH 3) 2O through the hydrogen bond. The spectrum of the aniline–(CH 3) 2O + gave only one strong absorption at 3430 cm −1. This band has been assigned to the stretching vibration of the free NH bond of aniline. The red shift of this band agrees with that expected from the correlation between the red shift and the proton affinity of interacting molecule obtained for the NH-σ type hydrogen bond.