Infrared spectra of X·CO·Ar cluster anions (X=Cl,Br,l)

The analysis of ion-clusters of the heavier halide anions with CO using argon (Ar) evaporation from its complexes upon infrared excitation, was discussed. It was found that the asymmetric stretch vibrational mode of the CO was red shifted from the frequency of free CO , with the red-shift increasing toward the lighter halide ions. In the region of the fermi resonance of the combination bands of the asymmetric stretch vibration, a similar red-shifting trend was repeated with two quanta of the bending vibration. Results showed that a weaker coupling of the modes was found in the halide complexes by the splitting of combination band fermi resonance.