AN INFRARED FAR-INFRARED DOUBLE-RESONANCE STUDY ON (NH3)2 IN A JET

An infrared-far-infrared double resonance experiment on (NH3)2 in a jet was performed. From the results, the nature of the tunneling splitting detected in former IR and FIR studies was identified. It was found that the (NH3)2 complex exhibits the following feasible motions: internal rotation of each monomer. interchange tunneling, and inversion tunneling. The rigid structure was classified in C(s), where a plane of symmetry is assumed. The FIR transitions reported so far and three new bands reported in this work could be assigned within the group G144. It is found that the inversion splitting for some of the bands is almost quenched. Upon excitation of the nu-2 umbrella motion the inversion splitting amounts to 3.7 cm-1.