ACCOUNTING FOR TUNNELING SPLITTINGS IN THE ROTATIONAL SPECTRUM OF C2H3+

New measurements have been carried out in the rotational spectrum of C 2H3+ using a negative glow discharge. An improved experimental resolut ion made it possible to observe the small splitting due to the large-a mplitude proton migration motion for a larger number of lines than in previous studies. These new measurements along with existing ones were analyzed using an internal-axis-method-like approach which allowed us to reproduce the observed splittings within the experimental resoluti on. This theoretical approach provided us with crucial information on the proton trajectories along the tunneling path. (C) 1996 Academic Pr ess, Inc.